U.S. patent application number 14/323333 was filed with the patent office on 2016-01-07 for nozzle design for ionic liquid catalyzed alkylation.
This patent application is currently assigned to Chevron U.S.A. Inc.. The applicant listed for this patent is Moinuddin Ahmed, Bong Kyu Chang, Michael John Girgis, Huping Luo, Donald Henry Mohr, Krishniah Parimi, Hye Kyung Cho Timken. Invention is credited to Moinuddin Ahmed, Bong Kyu Chang, Michael John Girgis, Huping Luo, Donald Henry Mohr, Krishniah Parimi, Hye Kyung Cho Timken.
Application Number | 20160002125 14/323333 |
Document ID | / |
Family ID | 52682909 |
Filed Date | 2016-01-07 |
United States Patent
Application |
20160002125 |
Kind Code |
A1 |
Luo; Huping ; et
al. |
January 7, 2016 |
NOZZLE DESIGN FOR IONIC LIQUID CATALYZED ALKYLATION
Abstract
Systems for ionic liquid catalyzed hydrocarbon conversion
comprise a reactor vessel, a mixing device in fluid communication
with the reactor vessel, and at least one circulation loop in fluid
communication with the reactor vessel and the mixing device. The
mixing device may comprise an upper venturi, at least one feed
injection component, and a lower venturi. Such systems may be used
for ionic liquid catalyzed alkylation reactions. Processes for
ionic liquid catalyzed hydrocarbon conversion are also
disclosed.
Inventors: |
Luo; Huping; (Richmond,
CA) ; Ahmed; Moinuddin; (Hercules, CA) ;
Parimi; Krishniah; (Alamo, CA) ; Chang; Bong Kyu;
(Novato, CA) ; Girgis; Michael John; (Richmond,
CA) ; Mohr; Donald Henry; (Orinda, CA) ;
Timken; Hye Kyung Cho; (Albany, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Luo; Huping
Ahmed; Moinuddin
Parimi; Krishniah
Chang; Bong Kyu
Girgis; Michael John
Mohr; Donald Henry
Timken; Hye Kyung Cho |
Richmond
Hercules
Alamo
Novato
Richmond
Orinda
Albany |
CA
CA
CA
CA
CA
CA
CA |
US
US
US
US
US
US
US |
|
|
Assignee: |
Chevron U.S.A. Inc.
San Ramon
CA
|
Family ID: |
52682909 |
Appl. No.: |
14/323333 |
Filed: |
July 3, 2014 |
Current U.S.
Class: |
585/447 ;
422/187; 422/224; 585/520; 585/653; 585/720; 585/734; 585/752 |
Current CPC
Class: |
C07C 2527/06 20130101;
B01F 2015/0221 20130101; B01J 2219/00103 20130101; C07C 5/277
20130101; C10G 2300/4081 20130101; C07C 2/70 20130101; B01F 5/048
20130101; B01J 19/26 20130101; B01F 5/0652 20130101; B01J 19/24
20130101; C07C 2/62 20130101; C10G 29/205 20130101; B01J 2219/24
20130101; C07C 2/08 20130101; C07C 4/06 20130101 |
International
Class: |
C07C 2/62 20060101
C07C002/62; B01J 19/24 20060101 B01J019/24; C07C 5/27 20060101
C07C005/27; C07C 2/70 20060101 C07C002/70; C07C 2/08 20060101
C07C002/08; B01J 19/26 20060101 B01J019/26; C07C 4/06 20060101
C07C004/06 |
Claims
1. A system for ionic liquid catalyzed hydrocarbon conversion, the
system comprising: a reactor vessel having a top; and a mixing
device disposed at the top of the reactor vessel, wherein the
mixing device comprises: an upper venturi having an axial outlet at
the upper venturi distal end, the upper venturi distal end disposed
within the reactor vessel, at least one feed injection array
disposed within the reactor vessel, each said feed injection array
coaxial with the upper venturi, and a lower venturi having an axial
inlet at the lower venturi proximal end, the lower venturi proximal
end disposed within the reactor vessel, wherein: the lower venturi
inlet is spaced radially outward from the upper venturi outlet to
define an inter-venturi channel between the upper venturi distal
end and the lower venturi proximal end, the lower venturi is
coaxial with the upper venturi, the mixing device is configured for
projecting a central jet of a first liquid downward from the upper
venturi outlet into the lower venturi, and each said feed injection
array is configured for projecting a second liquid toward an axis
of the upper venturi.
2. (canceled)
3. The system according to claim 1, wherein the lower venturi inlet
is disposed at the same elevation or about the same elevation as
the upper venturi outlet.
4. The system according to claim 1, wherein: the lower venturi has
a lower venturi constriction point, the at least one feed injection
array comprises a single feed injection array, and the single feed
injection array is disposed either at a first elevation of the
mixing device or at a second elevation of the mixing device, and
wherein: the first elevation is at the same elevation or about the
same elevation as the lower venturi inlet, and the second elevation
is at the same elevation or about the same elevation as the lower
venturi constriction point.
5. The system according to claim 1, wherein the at least one feed
injection array comprises: a first feed injection array disposed at
a first elevation of the mixing device, and a second feed injection
array disposed at a second elevation of the mixing device.
6. The system according to claim 5, wherein: the first elevation is
at the same elevation or about the same elevation as the lower
venturi inlet, the lower venturi has a lower venturi constriction
point at an elevation below the lower venturi inlet, and the second
elevation is at the same elevation or about the same elevation as
the lower venturi constriction point.
7. (canceled)
8. (canceled)
9. (canceled)
10. The system according to claim 1, wherein each said feed
injection array comprises from six (6) to 50 feed injection
nozzles.
11. (canceled)
12. (canceled)
13. (canceled)
14. The system according to claim 1, further comprising: a
circulation loop in fluid communication with the reactor vessel and
the mixing device, the circulation loop having a first loop end
coupled to a vessel outlet of the reactor vessel for withdrawing
reactor effluent from the reactor vessel into the circulation loop,
and the circulation loop further having a second loop end coupled
to the mixing device, wherein the circulation loop comprises: an
ionic liquid catalyst inlet configured for adding fresh ionic
liquid catalyst to the reactor effluent, wherein the first liquid
comprises the reactor effluent in combination with the fresh ionic
liquid catalyst, and a heat exchanger configured for cooling the
first liquid.
15. The system according to claim 14, further comprising: an ionic
liquid/hydrocarbon separator in fluid communication with the
circulation loop, wherein: the ionic liquid/hydrocarbon separator
is external to the circulation loop, the system is configured for
feeding a portion of the reactor effluent from the circulation loop
to the ionic liquid/hydrocarbon separator, and the ionic
liquid/hydrocarbon separator is configured for separating the
portion of reactor effluent into an ionic liquid catalyst phase and
a hydrocarbon phase.
16. The system according to claim 15, further comprising: a
fractionation unit in fluid communication with the ionic
liquid/hydrocarbon separator, wherein: the fractionation unit
comprises one or more distillation columns, and the fractionation
unit is configured for separating an alkylate product from the
hydrocarbon phase.
17. The system according to claim 14, further comprising a static
mixer in fluid communication with the heat exchanger and the mixing
device.
18. The system according to claim 1, wherein: the system
additionally comprises a circulation loop in fluid communication
with the reactor vessel, and wherein: each said feed injection
array comprises a plurality of feed injection nozzles; each said
feed injection array is configured for projecting a plurality of
lateral jets of a second liquid toward the axis of the upper
venturi; the circulation loop comprises a heat exchanger in fluid
communication with the reactor vessel; the heat exchanger is
configured for cooling reactor effluent of the reactor vessel; the
circulation loop is in fluid communication with the mixing device
for delivering cooled reactor effluent to the mixing device; and
the first liquid comprises the cooled reactor effluent.
19. The system according to claim 18, wherein: the mixing device is
configured for projecting the central jet axially downward from the
upper venturi outlet into the lower venturi inlet, and the axis of
each said feed injection nozzle intersects the axis of the upper
venturi at a common intersection at an elevation below the upper
venturi outlet.
20. The system according to claim 18, wherein: the lower venturi
proximal end is disposed at the same elevation or about the same
elevation as the upper venturi distal end, the at least one feed
injection array is at the same elevation or about the same
elevation as the lower venturi proximal end, and the plurality of
feed injection nozzles terminate at the same radial location or
about the same radial location as the perimeter of the upper
venturi outlet.
21. The system according to claim 1, wherein: the system further
comprises a vessel outlet and a circulation loop in fluid
communication with the vessel outlet; the mixing device is in fluid
communication with the reactor vessel; the system is configured for
withdrawing a reactor effluent from the reactor vessel via the
vessel outlet into the circulation loop; the circulation loop
comprises a heat exchanger configured for cooling withdrawn reactor
effluent; the circulation loop is configured for recirculating at
least a portion of the withdrawn reactor effluent to the mixing
device to provide an external recirculation stream to the reactor
vessel; the external recirculation stream comprises the withdrawn
reactor effluent; the upper venturi has an axial upper venturi
inlet at the upper venturi proximal end and is in fluid
communication with the circulation loop for receiving the external
recirculation stream at the axial upper venturi inlet; the upper
venturi is configured for projecting a central jet of the external
recirculation stream axially downward from the upper venturi
outlet; and each said feed injection array is configured for
simultaneously projecting a plurality of lateral jets of
hydrocarbon feed toward the central jet of the external
recirculation stream.
22. The system according to claim 21, wherein: the lower venturi
inlet is disposed at the same elevation or about the same elevation
as the upper venturi outlet, each of the lower venturi inlet and
the upper venturi outlet is at least substantially circular, the
inter-venturi channel is at least substantially annular, and the
inter-venturi channel is configured for circulation therethrough of
an internal recirculation stream of the reactor vessel.
23. The system according to claim 1, wherein the feed injection
array comprises a feed injection annulus having at least one feed
injection port.
24. The system according to claim 23, wherein the at least one feed
injection port comprises an annular slit in an inner portion of the
feed injection annulus.
25. The system according to claim 23, wherein the feed injection
annulus has from two (2) to 50 of said feed injection ports.
26. The system according to claim 25, wherein said feed injection
ports are symmetrically arranged on an inner portion of the feed
injection annulus.
27. The system according to claim 23, wherein the second liquid is
projected as a jet from each said feed injection port.
28. The system according to claim 23, wherein: the feed injection
annulus is coaxial with the upper venturi, and the system is
configured such that at least one jet of the second liquid collides
with the central jet.
29. The system according to claim 23, wherein the feed injection
annulus is disposed at the same elevation or about the same
elevation as the lower venturi inlet.
30. (canceled)
31. The system according to claim 23, wherein the lower venturi
inlet is disposed at the same elevation or about the same elevation
as the upper venturi outlet.
32. The system according to claim 23, further comprising: a
circulation loop in fluid communication with the reactor vessel and
the mixing device, the circulation loop having a first loop end
coupled to a vessel outlet of the reactor vessel for withdrawing
reactor effluent from the reactor vessel into the circulation loop,
and the circulation loop further having a second loop end coupled
to the mixing device, wherein the circulation loop comprises: an
ionic liquid catalyst inlet configured for adding fresh ionic
liquid catalyst to the reactor effluent, and a heat exchanger
configured for cooling the first liquid, wherein the first liquid
comprises the reactor effluent in combination with the fresh ionic
liquid catalyst, and the second liquid comprises a hydrocarbon
feed.
33. The system according to claim 32, further comprising: an ionic
liquid/hydrocarbon separator in fluid communication with the
circulation loop, wherein: the ionic liquid/hydrocarbon separator
is external to the circulation loop, the system is configured for
feeding a portion of the reactor effluent from the circulation loop
to the ionic liquid/hydrocarbon separator, and the ionic
liquid/hydrocarbon separator is configured for separating the
portion of reactor effluent into an ionic liquid catalyst phase and
a hydrocarbon phase.
34. The system according to claim 33, further comprising: a
fractionation unit in fluid communication with the ionic
liquid/hydrocarbon separator, wherein: the fractionation unit
comprises one or more distillation columns, and the fractionation
unit is configured for separating an alkylate product from the
hydrocarbon phase.
35. A process for ionic liquid catalyzed hydrocarbon conversion,
comprising: a) withdrawing reactor effluent from a reactor vessel,
the reactor effluent comprising unreacted hydrocarbons from a
hydrocarbon feed; b) adding ionic liquid catalyst to the reactor
effluent to provide an external recirculation stream; c)
introducing the external recirculation stream into a mixing device,
the mixing device in fluid communication with the reactor vessel,
wherein the mixing device comprises an upper venturi having an
axial outlet at the upper venturi distal end and a lower venturi
having an axial inlet at the lower venturi proximal end; d)
projecting a central jet of the external recirculation stream
downward from the upper venturi outlet into the lower venturi; e)
circulating an internal recirculation stream through the lower
venturi via an inter-venturi channel that is provided by the lower
venturi inlet being spaced radially outward from the upper venturi;
and f) concurrently with the projecting of the central jet,
projecting a hydrocarbon feed toward the central jet such that the
hydrocarbon feed collides with the central jet, wherein: the upper
venturi distal end and the lower venturi proximal end are disposed
within the reactor vessel, and the lower venturi is coaxial with
the upper venturi.
36. The process according to claim 35, wherein: the central jet
comprises an ionic liquid/hydrocarbon emulsion comprising droplets
of the ionic liquid catalyst, and step f) comprises contacting the
hydrocarbon feed with the ionic liquid catalyst under alkylation
conditions to provide an alkylate product.
37. (canceled)
38. (canceled)
39. The process according to claim 35, wherein: the mixing device
further comprises a feed injection array disposed within the
reactor vessel, the feed injection array comprises a plurality of
feed injection nozzles, and step f) comprises projecting the
hydrocarbon feed toward the central jet via the feed injection
nozzles.
40. The process according to claim 35, wherein: the mixing device
further comprises a feed injection annulus disposed within the
reactor vessel, the feed injection annulus having at least one feed
injection port, and step f) comprises projecting the hydrocarbon
feed toward the central jet via the at least one feed injection
port.
41. The process according to claim 35, wherein the central jet
comprises an ionic liquid/hydrocarbon emulsion comprising droplets
of the ionic liquid catalyst having a diameter in the range from
1-1000 microns.
42. The process according to claim 35, wherein the ionic liquid
catalyzed hydrocarbon conversion is selected from the group
consisting of: paraffin alkylation, paraffin isomerization, olefin
oligomerization, cracking of olefins or paraffins, and aromatic
alkylation.
43. The process according to claim 36, wherein: the ionic liquid
catalyzed hydrocarbon conversion comprises paraffin alkylation, the
hydrocarbon feed comprises at least one C.sub.2-C.sub.10 olefin and
at least one C.sub.4-C.sub.10 isoparaffin, the ionic liquid
catalyst comprises a chloroaluminate ionic liquid, and the
alkylation conditions comprise a temperature in the range from
-40.degree. C. to 150.degree. C., and a pressure in the range from
atmospheric pressure to 8000 kPa.
44. The process according to claim 35, further comprising: g)
feeding a portion of the reactor effluent to an ionic
liquid/hydrocarbon separator; h) via the ionic liquid/hydrocarbon
separator, separating the portion of reactor effluent into an ionic
liquid catalyst phase and a hydrocarbon phase; and i) via a
fractionation unit, separating an alkylate product from the
hydrocarbon phase.
45. The system according to claim 1, wherein each said feed
injection array comprises a plurality of feed injection
nozzles.
46. The system according to claim 45, wherein the plurality of feed
injection nozzles of each said feed injection array are
symmetrically arranged.
47. The system according to claim 45, wherein the axis of each said
feed injection nozzle intersects the axis of the upper venturi at
an angle, .theta., in the range from 20.degree. to 90.degree..
48. The system according to claim 45, wherein the axis of each said
feed injection nozzle intersects the axis of the upper venturi at
an angle, .theta., in the range from 80.degree. to 90.degree..
49. The system according to claim 45, wherein each said feed
injection array is configured for projecting a plurality of lateral
jets of the second liquid toward the axis of the upper venturi.
50. The system according to claim 49, wherein: each said feed
injection nozzle projects one of said lateral jets, and each said
feed injection nozzle terminates at the same radial location or
about the same radial location as the perimeter of the upper
venturi outlet.
51. The system according to claim 49, wherein each said feed
injection nozzle terminates at a location radially inward from the
perimeter of the upper venturi outlet such that the central jet
collides with at least a terminal portion of each said feed
injection nozzle.
52. The system according to claim 49, wherein: the system is
configured such that each said lateral jet collides with the
central jet, and the system is further configured such that a first
liquid linear velocity of the central jet is at least substantially
equal to a second liquid linear velocity of each said lateral
jet.
53. The system according to claim 1, wherein the inter-venturi
channel is configured for circulation therethrough of an internal
recirculation stream of the reactor vessel.
Description
TECHNICAL FIELD
[0001] This disclosure relates to apparatus, systems, and processes
for ionic liquid catalyzed alkylation.
BACKGROUND
[0002] There is a need for apparatus and systems for the efficient
mixing of two or more immiscible liquids, such as ionic liquid
catalysts and hydrocarbon feeds for ionic liquid catalyzed
hydrocarbon conversion processes including ionic liquid catalyzed
alkylation.
SUMMARY
[0003] In an embodiment there is provided a system for ionic liquid
catalyzed hydrocarbon conversion, the system comprising a reactor
vessel having a top, and a mixing device disposed at the top of the
reactor vessel. The mixing device comprises an upper venturi having
an axial outlet at the upper venturi distal end, the upper venturi
distal end disposed within the reactor vessel. The mixing device
further comprises at least one feed injection array disposed within
the reactor vessel, wherein each feed injection array comprises a
plurality of feed injection nozzles. Each feed injection array is
coaxial with the upper venturi. The mixing device still further
comprises a lower venturi having an axial inlet at the lower
venturi proximal end, wherein the lower venturi proximal end is
disposed within the reactor vessel, and the lower venturi is
coaxial with the upper venturi. The mixing device is configured for
projecting a central jet of a first liquid downward from the upper
venturi outlet into the lower venturi, and each feed injection
array is configured for projecting a plurality of laterals jet of a
second liquid toward the axis of the upper venturi.
[0004] In another embodiment, there is provided a system for ionic
liquid catalyzed hydrocarbon conversion, the system comprising a
reactor vessel having a top, a mixing device disposed at the top of
the reactor vessel, and a circulation loop in fluid communication
with the reactor vessel. The mixing device comprises an upper
venturi having an axial outlet at the upper venturi distal end. The
upper venturi distal end is disposed within the reactor vessel. The
mixing device is configured for projecting a central jet of a first
liquid downward from the upper venturi outlet. The mixing device
further comprises at least one feed injection array disposed within
the reactor vessel. Each feed injection array comprises a plurality
of feed injection nozzles. Each feed injection array is configured
for projecting a plurality of lateral jets of a second liquid
toward the axis of the upper venturi. The mixing device still
further comprises a lower venturi having an axial inlet at the
lower venturi proximal end, the lower venturi being coaxial with
the upper venturi. The lower venturi inlet is spaced radially
outward from the upper venturi outlet to provide an inter-venturi
channel between the lower venturi and the upper venturi. The
circulation loop comprises a heat exchanger in fluid communication
with the reactor vessel, wherein the heat exchanger is configured
for cooling the reactor effluent of the reactor vessel. The
circulation loop is in fluid communication with the mixing device
for delivering cooled reactor effluent to the mixing device,
wherein the first liquid comprises the cooled reactor effluent.
[0005] In yet another embodiment, there is provided a system for
ionic liquid catalyzed hydrocarbon conversion, the system
comprising a reactor vessel having a top and a vessel outlet; a
mixing device in fluid communication with the reactor vessel,
wherein the mixing device is disposed at the top of the reactor
vessel; and a circulation loop in fluid communication with the
vessel outlet. The system is configured for withdrawing reactor
effluent from the reactor vessel via the vessel outlet into the
circulation loop. The circulation loop comprises a heat exchanger
configured for cooling withdrawn reactor effluent. The circulation
loop is configured for recirculating at least a portion of the
withdrawn reactor effluent to the mixing device to provide an
external recirculation stream to the reactor vessel, wherein the
external recirculation stream comprises the withdrawn reactor
effluent. The mixing device comprises an upper venturi having an
axial upper venturi inlet at the upper venturi proximal end and an
axial upper venturi outlet at the upper venturi distal end. The
upper venturi is in fluid communication with the circulation loop
for receiving the external recirculation stream at the upper
venturi inlet. The upper venturi is configured for projecting a
central jet of the external recirculation stream axially downward
from the upper venturi outlet, wherein the upper venturi outlet is
disposed within the reactor vessel. The mixing device further
comprises at least one feed injection array. Each feed injection
array comprises a plurality of feed injection nozzles, wherein the
axis of each feed injection nozzle intersects the axis of the upper
venturi. Each feed injection array is configured for simultaneously
projecting a plurality of lateral jets of hydrocarbon feed toward
the central jet of the external recirculation stream. The mixing
device still further comprises a lower venturi disposed coaxially
with the feed injection array and with the upper venturi, the lower
venturi having an axial lower venturi inlet at the lower venturi
proximal end. The lower venturi inlet is spaced radially outward
from the upper venturi outlet to define an inter-venturi channel
between the upper venturi distal end and the lower venturi proximal
end.
[0006] In still a further embodiment, there is provided a system
for ionic liquid catalyzed hydrocarbon conversion comprising a
reactor vessel having a top, and a mixing device disposed at the
top of the reactor vessel. The mixing device comprises an upper
venturi having an axial outlet at the upper venturi distal end, the
upper venturi distal end disposed within the reactor vessel; a feed
injection annulus disposed within the reactor vessel, the feed
injection annulus having at least one feed injection port; and a
lower venturi having an axial inlet at the lower venturi proximal
end, the lower venturi proximal end disposed within the reactor
vessel. The lower venturi is coaxial with the upper venturi. The
mixing device is configured for projecting a central jet of a first
liquid downward from the upper venturi outlet into the lower
venturi. The feed injection annulus is configured for projecting a
second liquid from each feed injection port toward the axis of the
upper venturi.
[0007] In yet a further embodiment, there is provided a process for
ionic liquid catalyzed hydrocarbon conversion, the process
comprising withdrawing reactor effluent from a reactor vessel, the
reactor effluent comprising unreacted hydrocarbons from a
hydrocarbon feed; adding ionic liquid catalyst to the reactor
effluent to provide an external recirculation stream; introducing
the external recirculation stream into a mixing device, the mixing
device in fluid communication with the reactor vessel, wherein the
mixing device comprises an upper venturi having an axial outlet at
the upper venturi distal end and a lower venturi having an axial
inlet at the lower venturi proximal end; projecting a central jet
of the external recirculation stream downward from the upper
venturi outlet into the lower venturi; and, concurrently with the
projecting of the central jet, projecting a hydrocarbon feed toward
the central jet such that the hydrocarbon feed collides with the
central jet, wherein the upper venturi distal end and the lower
venturi proximal end are disposed within the reactor vessel, and
the lower venturi is coaxial with the upper venturi.
[0008] Further embodiments of systems and processes for ionic
liquid catalyzed hydrocarbon conversion are described herein below
and shown in the Drawings. As used herein, the terms "comprising"
and "comprises" mean the inclusion of named elements or steps that
are identified following those terms, but not necessarily excluding
other unnamed elements or steps.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIGS. 1A-1D each schematically represents a system for ionic
liquid catalyzed hydrocarbon conversion, according to embodiments
of the present invention;
[0010] FIG. 2 schematically represents a mixing device having a
feed injection array, as seen from the side, for an ionic liquid
catalyzed hydrocarbon conversion system, according to an embodiment
of the present invention;
[0011] FIG. 3A schematically represents an upper venturi for a
mixing device in perspective view, according to an embodiment of
the present invention;
[0012] FIG. 3B schematically represents a mixing device in
sectional view, according to an embodiment of the present
invention;
[0013] FIG. 3C schematically represents an upper venturi in
sectional view, according to another embodiment of the present
invention;
[0014] FIG. 4A schematically represents a lower venturi for a
mixing device in perspective view, according to an embodiment of
the present invention;
[0015] FIG. 4B schematically represents a lower venturi for a
mixing device in sectional view in relation to an upper venturi
outlet, according to an embodiment of the present invention;
[0016] FIG. 4C schematically represents a lower venturi in
sectional view, according to another embodiment of the present
invention;
[0017] FIG. 5A shows the intersection of the axis of an upper
venturi with the axis of each of a plurality of feed injection
nozzles of a feed injection array, and FIG. 5B shows the
intersection of the axis of the upper venturi with the axis of each
of the feed injection nozzles, as seen along the line 5B-5B of FIG.
5A, according to an embodiment of the present invention;
[0018] FIG. 6A shows, in sectional view, an inter-venturi channel
in relation to an upper venturi and a lower venturi of a mixing
device, and FIG. 6B shows the inter-venturi channel in relation to
the upper venturi outlet and the lower venturi inlet as seen along
the line 6B-6B of FIG. 6A, according an embodiment of the present
invention;
[0019] FIG. 7A schematically represents a mixing device, in
sectional view, and FIG. 7B shows a feed injection array of the
mixing device as seen along the line 7B-7B of FIG. 7A, according an
embodiment of the present invention;
[0020] FIG. 8A schematically represents a portion of a mixing
device, in sectional view, and FIG. 8B shows a feed injection array
of the mixing device, as seen along the line 8B-8B of FIG. 8A,
according an embodiment of the present invention;
[0021] FIG. 9A schematically represents a portion of a mixing
device, and FIG. 9B shows a feed injection array of the mixing
device, as seen along the line 9B-9B of FIG. 9A, according an
embodiment of the present invention;
[0022] FIG. 10 schematically represents, in sectional view, a lower
venturi for a mixing device having a feed injection array at the
same elevation or about the same elevation as a constriction point
of the lower venturi, according an embodiment of the present
invention;
[0023] FIG. 11A shows, in perspective view, a terminal portion of a
feed injection nozzle, and FIG. 11B shows a nozzle outlet of a feed
injection nozzle as seen along the line 11B-11B of FIG. 11A,
according an embodiment of the present invention;
[0024] FIG. 12A schematically represents a mixing device having a
feed injection annulus, as seen from the side, for an ionic liquid
catalyzed hydrocarbon conversion system, according to an embodiment
of the present invention;
[0025] FIG. 12B schematically represents a portion of a mixing
device having a feed injection annulus, FIG. 12C shows the feed
injection annulus as seen along the line 12C-12C of FIG. 12B, and
FIGS. 12D-12G each show a feed injection annulus, as seen in
sectional view along the line 12D-G-12D-G of FIG. 12C, according to
various embodiments of the present invention; and
[0026] FIG. 13 schematically represents a system and process for
ionic liquid catalyzed hydrocarbon conversion, according to another
embodiment of the present invention.
DETAILED DESCRIPTION
[0027] Ionic liquid catalysts may be useful for a range of
hydrocarbon conversion reactions, including alkylation reactions
for the production of alkylate, e.g., comprising gasoline blending
components, and the like. Systems for ionic liquid catalyzed
hydrocarbon conversion according to this disclosure may comprise a
reactor vessel, at least one mixing device per reactor vessel, and
at least one circulation loop per reactor vessel. Each circulation
loop may be in fluid communication with the reactor vessel and at
least one mixing device. Each mixing device may comprise an upper
venturi, at least one feed injection component, and a lower
venturi. In an embodiment, the at least one feed injection
component may comprise a feed injection array comprising a
plurality of feed injection nozzles. In another embodiment, the at
least one feed injection component may comprise a feed injection
annulus.
[0028] Mixing devices as disclosed herein provide for the rapid and
thorough mixing of ionic liquid catalyst and hydrocarbon reactants
so as to generate a large surface area of ionic liquid catalyst
phase in an ionic liquid/hydrocarbon mixture, thereby enabling
highly efficient ionic liquid catalyzed hydrocarbon conversion
processes on a commercial scale.
Systems for Ionic Liquid Catalyzed Alkylation
[0029] Although systems may be described herein primarily with
reference to ionic liquid catalyzed alkylation reactions, such
systems may also be applicable to other ionic liquid catalyzed
hydrocarbon conversion reactions as well as to other processes more
generally.
[0030] In an embodiment, a system for ionic liquid catalyzed
hydrocarbon conversion may comprise a reactor vessel and a mixing
device disposed at the top of the reactor vessel. The top of the
reactor vessel may also be referred to herein as the reactor vessel
top. The mixing device may be disposed vertically at the reactor
vessel top and the mixing device may extend distally from the
reactor vessel top into the reactor vessel. The mixing device may
also extend proximally above the reactor vessel top.
[0031] In an embodiment, each mixing device may comprise an upper
venturi, a plurality of feed injection nozzles, and a lower
venturi. In an embodiment, the lower venturi may be disposed below,
i.e., generally at a lower elevation than, the upper venturi. In an
embodiment, the upper venturi proximal end may be disposed above
the reactor vessel top such that the upper venturi proximal end is
located outside the reactor vessel, while the upper venturi distal
end and the entire lower venturi may be disposed below the reactor
vessel top and within the reactor vessel.
[0032] The upper venturi may have an axial inlet at the upper
venturi proximal end and an axial outlet at the upper venturi
distal end. The outlet of the upper venturi may be referred to
herein as the upper venturi outlet. The upper venturi distal end
may be disposed within the reactor vessel. In an embodiment, the
upper venturi may have a constriction point at an elevation above
the upper venturi outlet and below the upper venturi inlet. The
mixing device may be configured for projecting a central jet of a
first liquid downward from the upper venturi outlet into the lower
venturi. In an embodiment, the central jet may be projected
downward at high speed from the upper venturi outlet into the lower
venturi to form a local lower pressure region in the lower venturi
due to the Venturi effect. This lower pressure region may draw
liquid from the vicinity of the feed injection nozzles into the
lower venturi resulting in rapid mixing and mass transfer among
liquid streams in the lower venturi. The central jet of the first
liquid may be coaxial with the upper venturi.
[0033] In an embodiment, the mixing device may be configured for
projecting the central jet from the upper venturi on a continuous
or uninterrupted basis over an extended time period, e.g., between
shut-down operations of a reactor or system for service or
maintenance. In an embodiment, the first liquid (e.g., central jet)
may comprise an external recirculation stream of the reactor
vessel. In an embodiment, the external recirculation stream may
comprise reactor effluent from the reactor vessel in combination
with fresh ionic liquid catalyst, wherein the reactor effluent may
comprise unreacted hydrocarbons from a hydrocarbon feed. In an
embodiment, the central jet may consist essentially or entirely of
liquid(s), e.g., the first liquid may be at least substantially
free of gas(es) and gaseous phase materials.
[0034] The plurality of feed injection nozzles of the mixing device
may be configured or assembled into at least one feed injection
array, such that each feed injection array comprises a plurality of
the feed injection nozzles. Each feed injection array may be
disposed within the reactor vessel. Each feed injection array may
be configured for projecting a plurality of lateral jets of a
second liquid toward the axis of the upper venturi. In an
embodiment, each feed injection nozzle may be configured for
projecting one of the lateral jets toward the central jet. In an
embodiment, each feed injection nozzle may be configured for
projecting one of the lateral jets at high speed such that each
lateral jet impinges on the central jet with sufficient momentum to
create highly turbulent flow within the mixing device for optimal
mixing between the first and second liquid streams. In an
embodiment, each mixing device may be configured for projecting the
lateral jets on a continuous or uninterrupted basis over an
extended time period, e.g., between shut-down operations of the
reactor or system for service or maintenance. In an embodiment, the
second liquid may comprise a hydrocarbon feed, and the system may
be configured for ionic liquid catalyzed alkylation.
[0035] In an embodiment, the mixing device may be configured such
that the axis of each of the plurality of feed injection nozzles is
at an angle in the range from 0.degree. to 90.degree. to the axis
of the upper venturi. In a sub-embodiment, the axis of each of the
plurality of feed injection nozzles may intersect the axis of the
upper venturi at an angle, .theta. (see, e.g., FIG. 5A), wherein
.theta. is greater than (>) 0.degree. and not greater than
(.ltoreq.) 90.degree.. In another sub-embodiment, the axis of each
of the plurality of feed injection nozzles may intersect the axis
of the upper venturi at an angle, .theta., in the range from
20.degree. to 90.degree., or from 25.degree. to 90.degree., or from
30.degree. to 90.degree..
[0036] In a further sub-embodiment, the axis of each of the
plurality of feed injection nozzles may intersect the axis of the
upper venturi at an angle, .theta., in the range from 80.degree. to
90.degree., or from 85.degree. to 90.degree., or at substantially a
right angle. In an embodiment, the axis of each of the plurality of
feed injection nozzles may intersect the axis of the upper venturi
at an elevation below (distal to) the upper venturi outlet. In an
embodiment, the axis of each of the plurality of feed injection
nozzles of a given feed injection array may intersect the axis of
the upper venturi at a common intersection.
[0037] The lower venturi may have an axial inlet at the lower
venturi proximal end, wherein the lower venturi proximal end is
disposed within the reactor vessel. The inlet of the lower venturi
may be referred to herein as the lower venturi inlet. The lower
venturi may extend distally of the plurality of feed injection
nozzles. In an embodiment, each feed injection array and the lower
venturi may be disposed coaxially with the upper venturi.
[0038] In an embodiment, the plurality of feed injection nozzles of
a given feed injection array may be symmetrically arranged therein.
In an embodiment, the feed injection nozzles may be symmetrically
arranged in each feed injection array, and the feed injection
nozzles may be evenly spaced, or unevenly spaced, in the feed
injection array. In an embodiment, the ratio of a first liquid
linear velocity of the central jet from the upper venturi outlet to
a second liquid linear velocity of the lateral jets from the feed
injection nozzles may be in the range from 0.1-10, or from 0.2-5,
or from 0.8-1.2. In a sub-embodiment, the system may be configured
such that a first liquid linear velocity of the central jet from
the upper venturi outlet is at least substantially equal to a
second liquid linear velocity of each lateral jet from the feed
injection nozzles.
[0039] In an embodiment, each feed injection array may comprise
from six (6) to 50 of the feed injection nozzles, or from eight (8)
to 40 of the feed injection nozzles, or from 10 to 30 of the feed
injection nozzles. In an embodiment, the plurality of feed
injection nozzles of a given feed injection array may be arranged
annularly, e.g., in the form of a ring of the feed injection
nozzles per feed injection array. In an embodiment, each lateral
jet may be coaxial with the axis of its respective feed injection
nozzle. In an embodiment, the axis of each lateral jet may
intersect the axis of the central jet at an elevation below the
upper venturi outlet. In an embodiment, the axes of all the lateral
jets of a given feed injection array may intersect the axis of the
central jet at a common intersection.
[0040] In an embodiment, a feed injection array may be disposed at
the same elevation or about the same elevation as the lower venturi
inlet. In a sub-embodiment, the upper venturi outlet may be at the
same elevation or about the same elevation as the lower venturi
inlet. A feed injection array disposed at, or near, the upper
venturi outlet or the lower venturi inlet may allow for rapid or
instant mixing between the first liquid and the second liquid
within the lower venturi. By the term "elevation" is meant the
height at which an element, structure, feature, or component is
disposed, e.g., relative to the height of another element,
structure, feature, or component.
[0041] In another embodiment, the lower venturi has a constriction
point and a feed injection array may be disposed at the same
elevation or about the same elevation as the lower venturi
constriction point. The lower venturi constriction point may be at
an elevation below the lower venturi inlet and above the lower
venturi outlet. In a sub-embodiment, the feed injection nozzles of
a feed injection array may be disposed within the lower
venturi.
[0042] In an embodiment, the at least one feed injection array of a
given mixing device may comprise a single feed injection array,
wherein the single feed injection array may be disposed at a first
elevation of the mixing device or at a second elevation of the
mixing device. The first elevation may be at the same elevation or
about the same elevation as the lower venturi inlet, and the second
elevation may be at the same elevation or about the same elevation
as the lower venturi constriction point.
[0043] In another embodiment, the at least one feed injection array
of a given mixing device may comprise a first feed injection array
disposed at a first elevation of the mixing device and a second
feed injection array disposed at a second elevation of the mixing
device, wherein the first elevation may be at the same elevation or
about the same elevation as the lower venturi inlet and the second
elevation may be at the same elevation or about the same elevation
as the lower venturi constriction point. Liquid flow at, or near,
both the first elevation and the second elevation may be highly
turbulent.
[0044] In the context of describing the elevation of a feed
injection array relative to the lower venturi, the expression "the
same elevation or about the same elevation" means that a feed
injection array may be disposed at an elevation within a range
spanning a maximum distance above or below a given reference point
of the lower venturi as defined hereinbelow. For a feed injection
array disposed at a first elevation that is at the same elevation
or about the same elevation as the lower venturi inlet, the lower
venturi proximal end may be used as the reference point, and the
feed injection array may be disposed at an elevation within a range
spanning a distance not greater than (.ltoreq.) 0.5E.sub.A1 above
or below the lower venturi proximal end, wherein the distance
E.sub.A1 equals 20% of the diameter, D.sub.UO, of the upper venturi
outlet (E.sub.A1=0.2D.sub.UO). (See, for example, FIG. 4B.) For a
feed injection array disposed at a second elevation that is at the
same elevation or about the same elevation as the lower venturi
constriction point, the lower venturi constriction point may be
used as the reference point, and the feed injection array may be
disposed at an elevation within a range spanning a distance not
greater than (.ltoreq.) 0.5E.sub.A2 above or below the lower
venturi constriction point, wherein the distance E.sub.A2 equals
20% of the internal diameter, D.sub.LC, of the lower venturi
constriction point (E.sub.A2=0.2D.sub.LC). (See, for example, FIG.
4B.) One of ordinary skill will recognize that the distances
E.sub.A1 and E.sub.A2 are being used herein for relative
measurement only and accordingly have arbitrary units. Other
elevations for the feed injection array(s) relative to the lower
venturi are also possible. In an embodiment, the elevation of the
feed injection array(s) may be selected: 1) to increase or maximize
the volume of the internal recirculation stream drawn into the
mixing device by a lower pressure region formed within the lower
venturi due to the Venturi effect, and/or 2) to increase or
maximize the turbulence and the mixing intensity of fluid streams
within the lower venturi.
[0045] In an embodiment, each feed injection nozzle of the mixing
device may project one of the lateral jets toward the upper venturi
axis. In an embodiment, each of the feed injection nozzles may
terminate in a nozzle outlet (see, for example, FIGS. 11A-11B). In
an embodiment wherein the feed injection array may be disposed at
the same elevation or about the same elevation as the lower venturi
proximal end, each of the feed injection nozzles may terminate at
the same radial location or about the same radial location as the
perimeter of the upper venturi outlet. In the context of describing
the radial location of each nozzle terminus relative to the
perimeter of the upper venturi outlet, the expression "the same
radial location or about the same radial location" means that the
terminus of each feed injection nozzle may be disposed within a
radial distance not greater than (.ltoreq.) 0.2D.sub.UO radially
inward or radially outward from the perimeter of the upper venturi
outlet, wherein D.sub.UO is the diameter of the upper venturi
outlet. Other radial locations for the feed injection nozzles
relative to the perimeter of the upper venturi outlet are also
possible. In an embodiment, the radial location of the feed
injection nozzles may be selected to decrease or minimize the
mixing time between the liquid flow from the feed injection nozzles
and the flow from the upper venturi outlet.
[0046] In an embodiment wherein the feed injection array may be
disposed at the same elevation or about the same elevation as the
lower venturi constriction point, the terminus of each feed
injection nozzle may be disposed at a radial distance in the range
from 0.2 to 0.5D.sub.LC radially outward from the lower venturi
axis, A.sub.L, or in the range from 0.4D.sub.LC to 0.5D.sub.LC,
radially outward from the lower venturi axis, A.sub.L; wherein
D.sub.LC is the internal diameter of the lower venturi constriction
point.
[0047] In an embodiment, the lower venturi may have an axial inlet
at the lower venturi proximal end, such that the lower venturi
inlet is at the same elevation as the lower venturi proximal end.
In this context, the term "axial inlet" means that the lower
venturi inlet coincides with, or occupies the same space as, the
axis of the lower venturi. Similarly, in an embodiment the upper
venturi may have an axial outlet at the upper venturi distal end,
such that the upper venturi outlet is at the same elevation as the
upper venturi distal end. In this context, the term "axial outlet"
means that the upper venturi outlet coincides with, or occupies the
same space as, the axis of the upper venturi.
[0048] In an embodiment, the lower venturi proximal end may be
disposed at the same elevation or about the same elevation as the
upper venturi distal end. In the context of describing the
elevation of the lower venturi proximal end relative to the upper
venturi distal end, the expression "the same elevation or about the
same elevation" means that the lower venturi proximal end may be
disposed at an elevation within a range spanning a distance not
greater than (.ltoreq.) 0.5E.sub.L above or below the upper venturi
distal end, wherein the distance E.sub.L equals 20% of the
diameter, D.sub.LI, of the lower venturi inlet
(E.sub.L=0.2D.sub.LI) (see, for example, FIG. 3B). One of ordinary
skill will recognize that the distance E.sub.L is being used herein
for relative measurement only and accordingly has arbitrary units.
Other elevations for the lower venturi proximal end relative to the
upper venturi distal end are also possible.
[0049] In an embodiment, the lower venturi proximal end may be
spaced radially outward from the upper venturi distal end to
provide an inter-venturi channel; or, stated differently: the lower
venturi inlet may be spaced radially outward from the upper venturi
outlet to provide the inter-venturi channel. In an embodiment, the
inter-venturi channel may be configured to allow liquid(s) to be
drawn therethrough into the lower venturi, for example, via the
Venturi effect. In an embodiment, each of the upper venturi outlet
and the lower venturi inlet may be circular, and the inter-venturi
channel may comprise an annular or substantially annular
channel.
[0050] In an embodiment, the system may further comprise a
circulation loop in fluid communication with the reactor vessel and
the mixing device. The circulation loop may have a first loop end
coupled to a vessel outlet of the reactor vessel for withdrawing
reactor effluent from the reactor vessel into the circulation loop.
The circulation loop may further have a second loop end coupled to
the mixing device for introducing the first liquid into the reactor
vessel via the mixing device. In an embodiment, the circulation
loop may comprise a loop outlet, an ionic liquid catalyst inlet, a
circulation pump, a heat exchanger, and at least one circulation
loop conduit (see, for example, FIG. 1D).
[0051] In an embodiment, the loop outlet may be configured for
removing a portion of the withdrawn reactor effluent from the
circulation loop. In an embodiment, the ionic liquid catalyst inlet
may be configured for adding fresh ionic liquid catalyst to the
withdrawn reactor effluent within the circulation loop to provide
the first liquid, i.e., the first liquid may comprise the withdrawn
reactor effluent in combination with the fresh ionic liquid
catalyst. In an embodiment, the first liquid may be delivered, via
the circulation loop and the mixing device, to the top of the
reactor vessel to provide an external recirculation stream.
[0052] In an embodiment, the heat exchanger may be configured for
cooling the first liquid within the circulation loop. In an
embodiment, the least one circulation loop conduit may be coupled
to, and in fluid communication with, each of the vessel outlet, the
circulation pump, the heat exchanger, and the mixing device. In an
embodiment, the circulation pump may be configured for pumping the
first liquid through the circulation loop, e.g., to the heat
exchanger and the mixing device.
[0053] In an embodiment, the system may comprise a plurality of the
circulation loops per reactor vessel, wherein each circulation loop
may be in fluid communication with the reactor vessel and at least
one mixing device. In an embodiment, the system may further
comprise a static mixer in fluid communication with the heat
exchanger and the mixing device. In an embodiment, the static mixer
may be disposed downstream from the heat exchanger and upstream
from the mixing device.
[0054] In a further embodiment of a system for ionic liquid
catalyzed hydrocarbon conversion, the system may comprise a reactor
vessel having a top, at least one mixing device, and at least one
circulation loop. Each mixing device may be disposed at the top of
the reactor vessel. Each circulation loop may be in fluid
communication with the reactor vessel. Each mixing device may
comprise an upper venturi, at least one feed injection array, and a
lower venturi. The upper venturi may have an axial outlet at the
upper venturi distal end, and the upper venturi may be disposed
vertically at the top of the reactor vessel such that the upper
venturi outlet is inside the reactor vessel.
[0055] The system may be configured for projecting a central jet of
a first liquid downward from the upper venturi outlet. The lower
venturi may have an axial inlet at the lower venturi proximal end,
and the central jet of the first liquid may be projected downward
in an axial direction from the upper venturi outlet into the lower
venturi inlet. Each feed injection array may comprise a plurality
of feed injection nozzles. Each feed injection array may be
disposed within the reactor vessel. Each feed injection array may
be configured for projecting a plurality of lateral jets of a
second liquid toward the upper venturi axis, wherein the central
jet of the first liquid may be coaxial with the upper venturi.
[0056] The lower venturi may be disposed coaxially with the upper
venturi. The lower venturi inlet may be spaced radially outward
from the upper venturi outlet to provide or define an inter-venturi
channel between the lower venturi and the upper venturi. In an
embodiment, the lower venturi proximal end may be disposed at the
same elevation or about the same elevation as the upper venturi
distal end. In another embodiment, the lower venturi proximal end
may be disposed at an elevation below the upper venturi distal end.
In a further embodiment, the lower venturi proximal end may be
disposed at an elevation above the upper venturi distal end, and in
a sub-embodiment the lower venturi proximal end may be disposed at
an elevation between the upper venturi constriction point and the
upper venturi distal end.
[0057] Each circulation loop may comprise a heat exchanger, in
fluid communication with the reactor vessel, for cooling reactor
effluent from the reactor vessel to provide cooled reactor
effluent. The circulation loop may be in fluid communication with
the mixing device for delivering the cooled reactor effluent
thereto. In an embodiment, the first liquid (e.g., central jet)
projected from the upper venturi outlet may comprise the cooled
reactor effluent in combination with fresh ionic liquid catalyst.
The central jet of the first liquid may be projected into the
reactor vessel via the mixing device.
[0058] According to yet another embodiment of a system for ionic
liquid catalyzed hydrocarbon conversion, the system may comprise a
reactor vessel having a top and a vessel outlet, at least one
mixing device in fluid communication with the reactor vessel, and a
circulation loop in fluid communication with the vessel outlet and
the mixing device. Each mixing device may be disposed at the top of
the reactor vessel.
[0059] The circulation loop may be in fluid communication with the
vessel outlet. The system may be configured for withdrawing reactor
effluent from the reactor vessel via the vessel outlet into the
circulation loop. The circulation loop may comprise a heat
exchanger configured for cooling withdrawn reactor effluent. The
circulation loop may be configured for recirculating at least a
portion of the withdrawn reactor effluent to the mixing device to
provide an external recirculation stream to the reactor vessel,
wherein the external recirculation stream may comprise the
withdrawn reactor effluent. The reactor vessel may also have an
internal recirculation stream.
[0060] The expression "internal recirculation stream" may be used
herein to refer to a stream of liquid within the reactor vessel
that flows through and around the mixing device. In an embodiment,
the internal recirculation stream may flow downward through the
inter-venturi channel into the lower venturi, downward through the
interior of the lower venturi, and out of the lower venturi outlet.
The flow rate of the internal recirculation stream may be
quantified as the volume of liquid flowing through the
inter-venturi channel per unit time. The flow rate of the external
recirculation stream may be quantified as the volume of liquid
flowing from the upper venturi outlet per unit time. The ratio of
the flow rate of the internal recirculation stream to the flow rate
of the external recirculation stream may typically be in the range
from 0.1 to 10, or from 0.2 to 5, or from 0.25 to 4.
[0061] In an embodiment, apart from the mixing device(s) and any
reactor monitoring instrumentation and the like, the reactor vessel
may be entirely filled with liquid (e.g., comprising ionic liquid
catalyst, reactants, and alkylate product). The internal
recirculation stream of the reactor vessel may serve, inter alia,
to dilute the hydrocarbon feed in the mixing device and to decrease
the local olefin concentration so as to provide superior
product(s), e.g., alkylate. In an embodiment, the flow of the
internal recirculation stream within the reactor vessel may be
driven solely by the flow of liquid(s), including the external
recirculation stream, through the mixing device.
[0062] Each mixing device may comprise an upper venturi having an
axial upper venturi inlet and an axial upper venturi outlet, at
least one feed injection array, and a lower venturi disposed
coaxially with each feed injection array and the upper venturi. The
upper venturi may be in fluid communication with the circulation
loop for receiving the external recirculation stream, e.g., at the
upper venturi inlet. The upper venturi may be configured for
projecting a central jet of the external recirculation stream
(1.sup.st liquid) axially downward from the upper venturi outlet,
wherein the upper venturi outlet is disposed within the reactor
vessel.
[0063] Each feed injection array may comprise a plurality of feed
injection nozzles. In an embodiment, the axis of each feed
injection nozzle intersects the axis of the upper venturi (see, for
example, FIG. 5A). Each feed injection array may be configured for
simultaneously projecting a plurality of lateral jets of
hydrocarbon feed (second liquid) toward the central jet of the
external recirculation stream. That is to say, the system may be
configured to project a plurality of lateral jets from the feed
injection array concurrently with projection of the central jet
from the upper venturi outlet. In an embodiment, the system may be
configured such that the lateral jets of hydrocarbon feed collide
with the central jet of the external recirculation stream. Stated
differently, the system may be configured such that the central jet
collides with each of the lateral jets. The system may be further
configured for projecting both the central jet and the plurality of
lateral jets for extended time periods, e.g. continuously during
the entire time that the system is operating.
[0064] The lower venturi may comprise a lower venturi proximal end
having an axial lower venturi inlet. In an embodiment, the lower
venturi inlet may be disposed at the same elevation or about the
same elevation as the upper venturi outlet. In an embodiment, the
lower venturi inlet may be spaced radially outward from the upper
venturi outlet to provide or define an inter-venturi channel
between the upper venturi distal end and the lower venturi proximal
end. In an embodiment, each of the lower venturi inlet and the
upper venturi outlet may be at least substantially circular, and
the inter-venturi channel may be at least substantially annular. In
an embodiment, the inter-venturi channel may be configured for
circulation therethrough of the internal recirculation stream of
the reactor vessel (see, for example, FIGS. 6A-6B).
[0065] According to still a further embodiment of a system for
ionic liquid catalyzed hydrocarbon conversion, the system may
comprise a reactor vessel and a mixing device. The mixing device
may be disposed, e.g., vertically, at the reactor vessel top, the
mixing device may extend distally from the reactor vessel top into
the reactor vessel, and the mixing device may also extend
proximally above the reactor vessel top.
[0066] In an embodiment, each mixing device may comprise an upper
venturi, a feed injection annulus, and a lower venturi. In an
embodiment, the lower venturi may be disposed below, i.e.,
generally at a lower elevation than, the upper venturi. In an
embodiment, the upper venturi distal end, the feed injection
annulus, and the entire lower venturi may be disposed below the
reactor vessel top and within the reactor vessel.
[0067] The upper venturi may have an axial inlet at the upper
venturi proximal end and an axial outlet at the upper venturi
distal end. The upper venturi distal end may be disposed within the
reactor vessel. The upper venturi, the lower venturi, and the
reactor vessel may be juxtaposed and configured generally as
described hereinabove with reference to other embodiments of a
system for ionic liquid catalyzed hydrocarbon conversion and/or as
described with reference to FIG. 12A, infra. The mixing device may
be configured for projecting a central jet of a first liquid
downward from the upper venturi outlet into the lower venturi. The
central jet of the first liquid may be coaxial with the upper
venturi.
[0068] In an embodiment, the mixing device may be configured for
projecting the central jet from the upper venturi on a continuous
or uninterrupted basis, substantially as described hereinabove with
reference to other embodiments. The first liquid (e.g., central
jet) may comprise an external recirculation stream of the reactor
vessel. In an embodiment, the external recirculation stream may
comprise withdrawn reactor effluent in combination with fresh ionic
liquid catalyst.
[0069] The lower venturi may have an axial inlet at the lower
venturi proximal end, wherein the lower venturi proximal end is
disposed within the reactor vessel. The inlet of the lower venturi
may be referred to herein as the lower venturi inlet. The lower
venturi may be disposed coaxially with the upper venturi. In an
embodiment, the feed injection annulus may be disposed coaxially
with the upper venturi and at the same elevation or about the same
elevation as the lower venturi inlet, e.g., at, or near, the upper
venturi outlet. In the context of describing the elevation of a
feed injection annulus relative to the lower venturi, the
expression "the same elevation or about the same elevation" has the
same meaning as defined herein with respect to the elevation of a
feed injection array relative to the lower venturi (see, e.g.,
FIGS. 12A and 4B).
[0070] The feed injection annulus may have at least one feed
injection port. The feed injection annulus may be configured for
projecting a second liquid from each feed injection port toward the
axis of the upper venturi. In an embodiment, the second liquid may
be projected from each feed injection port as a jet of the second
liquid. In an embodiment, the system may be configured such that at
least one jet of the second liquid collides with the central jet of
the first liquid from the upper venturi outlet. Each mixing device
may be configured for projecting the second liquid on a continuous
or uninterrupted basis, substantially as described hereinabove with
respect to other embodiments of a system for ionic liquid catalyzed
hydrocarbon conversion. In an embodiment, the second liquid may
comprise a hydrocarbon feed, and the system may be configured for
ionic liquid catalyzed alkylation.
[0071] In an embodiment, the feed injection annulus may have a
single feed injection port. In a sub-embodiment, a single feed
injection port of the feed injection annulus may be in the form of
an annular slit in an inner portion of the feed injection annulus
(see, for example, FIGS. 12C-12D). In another embodiment, the feed
injection annulus may have from two (2) to 50 feed injection ports,
or from four (4) to 40 feed injection ports, or from six (6) to 30
feed injection ports.
[0072] In an embodiment, a plurality of the feed injection ports
may be symmetrically arranged on an inner portion of the feed
injection annulus. In an embodiment, the feed injection ports may
be evenly spaced, or unevenly spaced, on the feed injection
annulus. The feed injection ports may be of various shapes or
configurations, including substantially circular, oval, and square.
In another embodiment, the feed injection ports may be in the form
of elongated arcuate slits. In a further embodiment, one or more
feed injection ports may each be in the form of an annular slit. In
yet another embodiment, a given feed injection annulus may have a
combination of differently shaped feed injection ports. In general,
the size (area), arrangement, and/or number of the feed injection
ports of a given feed injection annulus may be selected as
appropriate in relation to various process parameters, including
the flow rate of the external- and internal recirculation streams
through the mixing device. In an embodiment, the system may be
configured such that a first liquid linear velocity of the central
jet from the upper venturi outlet is at least substantially equal
to a second liquid linear velocity of each jet of the second liquid
projected from the feed injection annulus.
[0073] In an embodiment, each feed injection port of the feed
injection annulus may be at the same radial location or about the
same radial location as the perimeter of the upper venturi outlet.
In the context of describing the radial location of each feed
injection port relative to the perimeter of the upper venturi
outlet, the expression "the same radial location or about the same
radial location" means that each feed injection port may be
disposed within a radial distance not greater than (.ltoreq.)
0.2D.sub.UO radially inward or radially outward from the perimeter
of the upper venturi outlet, wherein D.sub.UO is the diameter of
the upper venturi outlet. Other radial locations for the feed
injection port(s) relative to the perimeter of the upper venturi
outlet are also possible.
[0074] In an embodiment, the lower venturi inlet may be disposed at
the same elevation or about the same elevation as the upper venturi
outlet. In the context of describing the elevation of the lower
venturi proximal end relative to the upper venturi distal end, the
expression "the same elevation or about the same elevation" has the
same meaning as defined herein with respect to other embodiments of
a mixing device (see, e.g., FIG. 3B). Other elevations for the
lower venturi inlet relative to the upper venturi outlet are also
possible.
[0075] In an embodiment, the lower venturi inlet may be spaced
radially outward from the upper venturi outlet to provide an
inter-venturi channel. In an embodiment, the inter-venturi channel
may be configured as described hereinabove. In an embodiment, each
of the upper venturi outlet and the lower venturi inlet may be
circular, and the inter-venturi channel may comprise an annular or
substantially annular channel.
[0076] In an embodiment, the system may further comprise a
circulation loop in fluid communication with the reactor vessel and
the mixing device. The circulation loop may have a first loop end
coupled to a vessel outlet of the reactor vessel for withdrawing
reactor effluent from the reactor vessel into the circulation loop,
and a second loop end coupled to the mixing device. The circulation
loop may comprise an ionic liquid catalyst inlet configured for
adding fresh ionic liquid catalyst to withdrawn reactor effluent,
and a heat exchanger configured for cooling the first liquid (see,
for example, FIG. 1D).
[0077] According to yet a further embodiment, a process for ionic
liquid catalyzed hydrocarbon conversion, e.g., isoparaffin/olefin
alkylation, may be practiced using systems as disclosed herein.
Such systems may comprise a reactor vessel having a vessel outlet,
at least one mixing device in fluid communication with the reactor
vessel, and a circulation loop in fluid communication with the
vessel outlet and the mixing device. The mixing device may comprise
an upper venturi having an axial outlet at the upper venturi distal
end, and a lower venturi having an axial inlet at the lower venturi
proximal end. The upper venturi distal end and the lower venturi
proximal end may be disposed within the reactor vessel, and the
lower venturi may be coaxial with the upper venturi. The mixing
device may further comprise at least one feed injection component
disposed within the reactor vessel. In an embodiment, each mixing
device may be disposed vertically in the top of the reactor vessel.
Such systems may further comprise additional elements, features,
and characteristics as described herein and as shown in the
drawings.
[0078] Processes for ionic liquid catalyzed hydrocarbon conversion
may include: withdrawing reactor effluent from the reactor vessel
via the circulation loop, adding fresh ionic liquid catalyst to the
withdrawn reactor effluent to provide an external recirculation
stream, and introducing the external recirculation stream into the
mixing device. A portion of the withdrawn reactor effluent may be
removed from the circulation loop for fractionation to provide an
alkylate product. In an embodiment, the reactor effluent or
external recirculation stream may be cooled in the circulation loop
prior to introducing the external recirculation stream into the
mixing device.
[0079] In an embodiment, a process for ionic liquid catalyzed
hydrocarbon conversion may further include: projecting a central
jet of the external recirculation stream downward from the upper
venturi outlet into the lower venturi inlet; and, concurrently with
the projecting of the central jet, additionally projecting a
hydrocarbon feed toward the central jet such that the hydrocarbon
feed collides with the central jet. In an embodiment, the central
jet may be coaxial with the axis of the upper venturi.
[0080] The central jet may comprise an ionic liquid/hydrocarbon
emulsion comprising small to microscopic droplets of the ionic
liquid catalyst, e.g., having an ionic liquid catalyst droplet
diameter in the range from 1 to 1000 microns, or from 5 to 250
microns, or from 10 to 150 microns. In an embodiment, the
hydrocarbon feed may collide with the central jet, such that the
hydrocarbon feed contacts a large surface area of the ionic liquid
catalyst. Such contacting of the hydrocarbon feed with the ionic
liquid catalyst may be under alkylation conditions so as to provide
alkylate product(s).
[0081] Processes for ionic liquid catalyzed hydrocarbon conversion
may still further include circulating an internal recirculation
stream of the reactor vessel through the lower venturi of the
mixing device. Accordingly, both the external- and internal
recirculation streams may flow through the lower venturi. In an
embodiment, the ratio of the flow rate (vol. per unit time) of the
internal recirculation stream to the flow rate of the external
recirculation stream during processes as disclosed herein may
typically be in the range from 0.1 to 10, or from 0.2 to 5, or from
0.25 to 4. In an embodiment, the lower venturi inlet may be spaced
radially outward from the upper venturi outlet to provide an
inter-venturi channel, and the internal recirculation stream may be
circulated through the lower venturi via the inter-venturi
channel.
[0082] In an embodiment, the at least one feed injection component
of the mixing device may comprise a feed injection annulus having
at least one feed injection port. In an embodiment of a process for
ionic liquid catalyzed hydrocarbon conversion, the hydrocarbon feed
may be projected toward the central jet via the at least one feed
injection port of the feed injection annulus.
[0083] In another embodiment, the at least one feed injection
component of the mixing device may comprise a feed injection array
disposed within the reactor vessel, and the feed injection array
may comprise a plurality of feed injection nozzles. In an
embodiment of a process for ionic liquid catalyzed hydrocarbon
conversion, the hydrocarbon feed may be projected toward the
central jet, e.g., as a plurality of lateral jets, via the feed
injection nozzles.
[0084] In an embodiment, a feed injection array of the mixing
device may be disposed at the same elevation or about the same
elevation as the lower venturi inlet, and the feed injection
nozzles may terminate at a location radially inward from the
perimeter of the upper venturi outlet such that the central jet may
collide with at least a terminal portion of each feed injection
nozzle (see, for example, FIGS. 8A-8B). In another embodiment, the
feed injection array may be disposed at an elevation below the
lower venturi inlet, and the feed injection nozzles may extend
radially inward into the lower venturi such that at least one of
the external recirculation stream and the internal recirculation
stream may collide with at least a terminal portion of each feed
injection nozzle (see, for example, FIG. 10).
[0085] In an embodiment, the hydrocarbon feed may be introduced
directly into the lower venturi, e.g., via a plurality of feed
injection nozzles disposed within the lower venturi. In a
sub-embodiment, a plurality of the feed injection nozzles may be
disposed within the lower venturi at the same elevation or about
the same elevation as the lower venturi constriction point.
[0086] In an embodiment, the hydrocarbon feed may comprise at least
one C.sub.2-C.sub.10 olefin and at least one C.sub.4-C.sub.10
isoparaffin. In an embodiment, the ionic liquid catalyst may
comprise a chloroaluminate ionic liquid. In an embodiment, the
alkylation conditions may comprise a temperature in the range from
-40.degree. C. to 150.degree. C., and a pressure in the range from
atmospheric pressure to 8000 kPa. In an embodiment, the overall
ionic liquid catalyst volume in the reactor vessel may be
maintained in the range from 0.5 to 50 vol %, or from 1 to 10 vol
%, or from 2 to 6 vol %. Hydrocarbon feeds, ionic liquid catalysts,
and conditions for ionic liquid catalyzed alkylation are described
hereinbelow.
[0087] In an embodiment, a process for ionic liquid catalyzed
hydrocarbon conversion may still further include feeding a portion
of the reactor effluent from the circulation loop to an ionic
liquid/hydrocarbon separator; via the ionic liquid/hydrocarbon
separator, separating the portion of reactor effluent into an ionic
liquid catalyst phase and a hydrocarbon phase; and via a
fractionation unit, separating an alkylate product from the
hydrocarbon phase.
[0088] With reference to the drawings, FIGS. 1A-1D each
schematically represents a system for ionic liquid catalyzed
hydrocarbon conversion processes. With reference to FIG. 1A-1C, a
system 100 for ionic liquid catalyzed hydrocarbon conversion may
comprise a reactor vessel 200, at least one mixing device 300/300',
and at least one circulation loop 400. Mixing device 300/300'
provides for the rapid and thorough mixing of ionic liquid catalyst
and hydrocarbon reactants. As an example, mixing device 300/300'
may generate a large surface area of the ionic liquid catalyst
phase in an ionic liquid/hydrocarbon mixture, thereby providing for
the highly efficient performance of ionic liquid catalyzed
hydrocarbon conversion processes.
[0089] Reactor vessel 200 has a reactor vessel top (or upper cap)
202, and mixing device 300/300' may be disposed at reactor vessel
top 202. An upper (proximal) portion of mixing device 300/300' may
extend proximally above reactor vessel top 202. A lower (distal)
portion of mixing device 300/300' may be disposed within reactor
vessel 200. Reactor vessel 200 may be at least substantially filled
with liquid, and the portion of mixing device 300/300' within
reactor vessel 200 may be immersed in the liquid contents of
reactor vessel 200.
[0090] In an embodiment, reactor vessel 200 may be vertically
aligned having a height greater than its width, and mixing device
300/300' may be disposed at reactor vessel top 202. In a
sub-embodiment, mixing device 300/300' may be disposed vertically
at reactor vessel top 202 such that the axis of each mixing device
300/300' may be at least substantially parallel to the axis of
reactor vessel 200. In another sub-embodiment (not shown), mixing
device(s) 300/300' may be disposed at various angles with respect
to the axis of reactor vessel 200.
[0091] In an embodiment, reactor vessel 200 may be substantially
cylindrical. In an embodiment, system 100 may comprise a plurality
of mixing devices 300/300' per reactor vessel 200. As an example
only, with further reference to FIG. 1B two mixing devices
300a/300'a and 300b/300'b are shown at reactor vessel top 202, it
being understood that other numbers of mixing devices may similarly
be used. In an embodiment, system 100 may comprise a plurality of
mixing devices 300/300', wherein each of the mixing devices may be
disposed at substantially the same elevation with respect to
reactor vessel top 202.
[0092] Circulation loop 400 may be in fluid communication with
reactor vessel 200 for withdrawing liquid (e.g., reactor effluent)
from reactor vessel 200 into circulation loop 400. Mixing device
300/300' may be in fluid communication with reactor vessel 200.
Circulation loop 400 may further be in fluid communication with
mixing device 300/300' for recirculating the withdrawn liquid to
reactor vessel 200 via mixing device 300/300'. In an embodiment,
system 100 may comprise a plurality of circulation loops 400,
wherein each circulation loop 400 may be in fluid communication
with reactor vessel 200 and with at least one mixing device
300/300'. In embodiments of a system having a plurality of
circulation loops 400, each circulation loop 400 may have a
dedicated circulation pump and heat exchanger. In the embodiment of
FIG. 1C, two circulation loops 400, 400' are shown, it being
understood that other numbers of circulation loops may be used. In
an embodiment, each of a plurality of circulation loops may have
one or more dedicated mixing devices 300/300'.
[0093] FIG. 1D schematically represents a system 100 comprising a
reactor vessel 200 having a vessel outlet 204, a mixing device
300/300' disposed at reactor vessel top 202, and a circulation loop
400. In an embodiment, vessel outlet 204 may be at the opposite end
of reactor vessel 200 from mixing device 300/300', e.g., vessel
outlet 204 may be at the base (or lower cap) 203 of reactor vessel
200. A hydrocarbon feed 301 may be introduced into reactor vessel
200 via mixing device 300/300'. In an embodiment, the hydrocarbon
feed may comprise an olefin feed stream, an isoparaffin feed
stream, or a combination thereof, for ionic liquid catalyzed
alkylation, e.g., as described hereinbelow.
[0094] Circulation loop 400 may comprise a first loop end 400a
coupled to vessel outlet 204 and a second loop end 400b coupled to
mixing device 300/300'. Circulation loop 400 may further comprise a
loop outlet 402, an ionic liquid catalyst inlet 404, a circulation
pump 406, and a heat exchanger 408. Circulation loop 400 may still
further comprise at least one circulation loop conduit 410, e.g.,
for coupling components of circulation loop 400 to vessel outlet
204 and mixing device 300/300'.
[0095] Reactor effluent 206 may be withdrawn from reactor vessel
200 into circulation loop 400 via vessel outlet 204. Reactor
effluent 206 may comprise ionic liquid catalyst that has previously
contacted the hydrocarbon feed in reactor vessel 200. Fresh ionic
liquid catalyst 403 may be added to reactor effluent 206, within
circulation loop 400, via ionic liquid catalyst inlet 404 to
provide an external recirculation stream, R.sub.E. A portion of
withdrawn reactor effluent 206 may be removed from circulation loop
400, via loop outlet 402, e.g., for fractionation thereof to
provide an alkylate product. Loop outlet 402 and ionic liquid
catalyst inlet 404 may be disposed at various locations within
circulation loop 400 other than as shown in FIG. 1D.
[0096] With further reference to FIG. 1D, in an embodiment system
100 may further comprise a static mixer 412, in fluid communication
with circulation loop 400, for premixing the external recirculation
stream prior to introducing the external recirculation stream into
mixing device 300/300'. In an embodiment, static mixer 412 may be
disposed immediately upstream from, e.g., above, mixing device
300/300'. Although only one circulation loop 400 is shown in FIG.
1D, a plurality of circulation loops 400 may be used (see, for
example, FIG. 1C). In an embodiment, system 100 may be configured
for ionic liquid catalyzed alkylation reactions and processes.
Feeds, ionic liquid catalysts, and reaction conditions for ionic
liquid catalyzed alkylation are described hereinbelow.
[0097] FIG. 2 schematically represents a mixing device 300
comprising an upper venturi 310, at least one feed injection array
320, and a lower venturi 330. In an embodiment, each mixing device
300 may comprise a single upper venturi 310 and a single lower
venturi 330. Each feed injection array 320 may comprise a plurality
of feed injection nozzles 322 (see, e.g., FIGS. 5A-11B), such that
each mixing device 300 may comprise a plurality of feed injection
nozzles 322 per upper venturi 310/lower venturi 330. In an
embodiment, upper venturi 310 may be disposed vertically within
reactor vessel top 202. Upper venturi 310 may be affixed to, and
sealingly engaged with, reactor vessel top 202.
[0098] In FIG. 2 the axis of upper venturi 310 is indicated by the
line labeled A.sub.U. Lower venturi 330 may be coaxial with upper
venturi 310. In an embodiment, lower venturi 330 may be affixed to
upper venturi 310, e.g., using suitable support structures (not
shown), such as steel bars, and the like. Other mechanisms for
affixing or anchoring lower venturi 330 relative to upper venturi
310 are also possible. In an embodiment, lower venturi proximal end
330a may be disposed at the same elevation or about the same
elevation as upper venturi distal end 310b, e.g., as described with
reference to FIG. 3B, infra. In FIG. 2, lower venturi proximal end
330a may be shown below upper venturi distal end 310b for the sake
of clarity of illustration.
[0099] According to various embodiments, mixing device 300 may have
a first feed injection array 320 at the same elevation or about the
same elevation as lower venturi proximal end 330a, and/or mixing
device 300 may have a second feed injection array 320' at the same
elevation or about the same elevation as lower venturi constriction
point 336, e.g., as described hereinabove and with respect to FIG.
4B, infra. Mixing device 300 is not limited to a particular number,
arrangement, or location of feed injection array(s). As shown,
lower venturi constriction point 336 may be at an elevation below
lower venturi inlet 332 and above lower venturi outlet 334. In an
embodiment, lower venturi constriction point 336 may be at an
elevation in the range from 10% to 90% of the length, L.sub.L, of
lower venturi 330 below lower venturi inlet 332.
[0100] In an embodiment, upper venturi distal end 310b, feed
injection array(s) 320/320', and lower venturi 330 may be disposed
within reactor vessel 200. In an embodiment, feed injection
array(s) 320/320' may be disposed coaxially with both upper venturi
310 and lower venturi 330. Feed injection array(s) 320/320' may be
affixed, attached, or coupled to upper venturi 310 and/or to lower
venturi 330, for example, according to the number, arrangement, and
elevation of feed injection array(s) 320/320' relative to upper
venturi 310 and lower venturi 330.
[0101] FIG. 3A schematically represents an upper venturi for a
mixing device in perspective view, and FIG. 3B schematically
represents a mixing device in sectional view. FIG. 3C schematically
represents an upper venturi in sectional view according to another
embodiment. Upper venturi 310 is shown in isolation in FIG. 3A and
feed injection array(s) 320 are omitted from FIG. 3B for the sake
of clarity of illustration. With reference to FIGS. 3A-3B, upper
venturi 310 may have an axial inlet 312 at upper venturi proximal
end 310a and an axial outlet 314 at upper venturi distal end 310b.
Each of upper venturi inlet 312 and upper venturi outlet 314 may be
at least substantially circular. Upper venturi 310 may have a
length L.sub.U. Upper venturi inlet 312 and upper venturi outlet
314 have diameters D.sub.UI and D.sub.UO, respectively. In an
embodiment, the diameter, D.sub.UI, of upper venturi inlet 312 may
be greater than the diameter, D.sub.UO, of upper venturi outlet 314
(D.sub.UI>D.sub.UO).
[0102] In an embodiment, the vertical bar, E.sub.L, in FIG. 3B
indicates a range of elevations for locating lower venturi inlet
332 relative to upper venturi outlet 314, wherein the distance
corresponding to E.sub.L is vertically centered at the elevation of
upper venturi outlet 314. In an embodiment, upper venturi outlet
314 is axial and the elevation of upper venturi outlet 314
corresponds to the elevation of upper venturi distal end 310b.
Similarly, in an embodiment lower venturi inlet 332 is axial and
the elevation of lower venturi inlet 332 corresponds to the
elevation of lower venturi proximal end 330a. In FIGS. 3B and 4B,
lower venturi proximal end 330a may be shown as being slightly
below upper venturi distal end 310b for the sake of clarity of
illustration.
[0103] With further reference to FIG. 3B, in an embodiment lower
venturi proximal end 330a may be disposed at the same elevation or
about the same elevation as upper venturi distal end 310b such that
lower venturi proximal end 330a is disposed at an elevation within
a range spanning a distance not greater than (.ltoreq.) 0.5E.sub.L
above or below upper venturi distal end 310b, wherein the distance
E.sub.L equals 20% of the diameter, D.sub.LI, of the lower venturi
inlet (E.sub.L=0.2D.sub.LI). In other embodiments, the distance
E.sub.L may be equal to 50% of the diameter D.sub.LI
(E.sub.L=0.5D.sub.LI) or 100% of the diameter D.sub.LI
(E.sub.L=D.sub.LI). Other elevations of lower venturi inlet 332
relative to upper venturi outlet 314 are also possible.
[0104] Upper venturi 310 may further comprise a constriction point
316. Upper venturi constriction point 316 may be defined as the
point or location along upper venturi 310 where its internal
diameter, D.sub.UC, has tapered to a minimum. As shown, upper
venturi constriction point 316 may be at an elevation above upper
venturi distal end 310b. Tapering of the internal diameter of upper
venturi 310 may be linear, or non-linear, or a combination thereof.
The relationship between liquid velocity and pressure changes in a
venturi or venturi tube, e.g., according to the venturi effect, is
well known in the art.
[0105] In an embodiment, one or more portions of upper venturi 310
may be at least substantially non-tapered; for example, a proximal
portion and/or a distal portion of upper venturi 310 may be at
least substantially cylindrical (see, for example, FIG. 3A). In an
embodiment, the diameter, D.sub.UO, of upper venturi outlet 314 may
be the same or substantially the same as the internal diameter,
D.sub.UC, of upper venturi constriction point 316
(D.sub.UO=D.sub.UC). In another embodiment, upper venturi 310 may
be flared distal to upper venturi constriction point 316, such that
the diameter, D.sub.UO, of upper venturi outlet 314 may be greater
than the internal diameter, D.sub.UC, of upper venturi constriction
point 316 (D.sub.UO>D.sub.UC) (see, for example, FIG. 3C).
[0106] FIG. 4A shows a lower venturi of a mixing device in
perspective view, and FIG. 4B shows a lower venturi for a mixing
device in sectional view in relation to an upper venturi outlet.
FIG. 4C shows a lower venturi in sectional view according to
another embodiment. With reference to FIGS. 4A-4C, lower venturi
330 may comprise an axial inlet 332 at lower venturi proximal end
330a and an axial outlet 334 at lower venturi distal end 330b. Each
of lower venturi inlet 332 and lower venturi outlet 334 may be at
least substantially circular. Lower venturi 330 may further
comprise a constriction point 336. Lower venturi constriction point
336 may be defined as the location along lower venturi 330 where
the internal diameter, D.sub.LC, has tapered to a minimum. Tapering
of the internal diameter of lower venturi 330 may be linear, or
non-linear, or a combination thereof. In an embodiment, a portion
of lower venturi 330 may be at least substantially non-tapered. As
a non-limiting example, in an embodiment a portion of lower venturi
330 distal to lower venturi constriction point 336 may be at least
substantially cylindrical (see, e.g., FIG. 4C).
[0107] With further reference to FIG. 4B, lower venturi 330 may
have a length L.sub.L. Lower venturi constriction point 336 may
have an internal diameter D.sub.LC, and upper venturi outlet 314
may have a diameter D.sub.UO. According to various embodiments, the
vertical bars labeled E.sub.A1 and E.sub.A2 (FIG. 4B) may each
indicate a range of elevations for the location of feed injection
array(s) 320/320' relative to lower venturi proximal end 330a and
lower venturi constriction point 336, respectively. The distances
corresponding to E.sub.A1 and E.sub.A2 are vertically centered at
lower venturi proximal end 330a and lower venturi constriction
point 336, respectively. The bar labeled E.sub.A1 may be used to
represent a distance (arbitrary units) relative to the diameter,
D.sub.UO, of upper venturi outlet 314, and the bar labeled E.sub.A2
may be used to represent a distance (arbitrary units) relative to
the internal diameter, D.sub.LC, of lower venturi constriction
point 336.
[0108] In an embodiment, mixing device 300 may have a single feed
injection array 320 at an elevation within the bar labeled
E.sub.A1; in another embodiment, mixing device 300 may have a
single feed injection array 320' at an elevation within the bar
labeled E.sub.A2; and in yet another embodiment, mixing device 300
may have a first feed injection array 320 at an elevation within
the bar labeled E.sub.A1 as well as a second feed injection array
320' at an elevation within the bar labeled E.sub.A2.
[0109] In an embodiment, feed injection array 320 may be disposed
at the same elevation or about the same elevation as lower venturi
proximal end 330a such that feed injection array 320 is disposed at
an elevation within a range spanning a distance not greater than
(.ltoreq.) 0.5E.sub.A1 above or below lower venturi proximal end
330a, wherein E.sub.A1 equals 20% of the diameter, D.sub.UO, of
upper venturi outlet 314. In other embodiments, the distance
E.sub.A1 may be equal to 50% of the diameter D.sub.UO
(E.sub.A1=0.5D.sub.UO) or 100% of the diameter D.sub.UO
(E.sub.A1=D.sub.UO).
[0110] In another embodiment, feed injection array 320' may be
disposed at the same elevation or about the same elevation as lower
venturi constriction point 336 such that feed injection array 320'
is disposed at an elevation within a range spanning a distance not
greater than (.ltoreq.) 0.5E.sub.A2 above or below lower venturi
constriction point 336, wherein E.sub.A2 equals 20% of the internal
diameter, D.sub.LC, of lower venturi constriction point 336. In
other embodiments, the distance E.sub.A2 may be equal to 50% of the
internal diameter D.sub.LC (E.sub.A2=0.5D.sub.LC) or 100% of the
internal diameter D.sub.LC (E.sub.A2=D.sub.LC). Elevations for feed
injection array(s) 320, 320' other than those delineated by the
bars E.sub.A1 and E.sub.A2 of FIG. 4B are also possible.
[0111] In an embodiment, a feed injection array 320 for a mixing
device 300 may be configured such that the axis of each of the
plurality of feed injection nozzles 322 is at an angle in the range
from 0.degree. to 90.degree. to the axis of upper venturi 310. FIG.
5A shows a distal (lower) portion of an upper venturi 310 in
relation to a plurality of feed injection nozzles 322 of a feed
injection array 320. In an embodiment, the angle, .theta., between
the axis, A.sub.N, of each feed injection nozzle 322 and the axis,
A.sub.U, of upper venturi 310 may be greater than (>) 0.degree.
and not greater than (.ltoreq.) 90.degree., such that the axis of
each feed injection nozzle 322 intersects the axis of upper venturi
310 at an elevation below upper venturi outlet 314. In a
sub-embodiment, the angle of intersection, .theta., may be in the
range from 20.degree. to 90.degree., or from 25.degree. to
90.degree., or from 30.degree. to 90.degree.. In another
sub-embodiment, the angle of intersection, .theta., may be in the
range from 80.degree. to 90.degree., or from 85.degree. to
90.degree., or at least substantially a right angle.
[0112] With further reference to FIG. 5A, the axes, A.sub.N, of
feed injection nozzles 322a and 322c may intersect the axis,
A.sub.U, of upper venturi 310 at a common intersection at an
elevation below upper venturi outlet 314. In FIG. 5A, the arrow
R.sub.E indicates the downward direction of the central jet from
upper venturi 310.
[0113] FIG. 5B shows the intersection of the axis of the upper
venturi with the axis of each feed injection nozzle, as seen along
the line 5B-5B of FIG. 5A. In FIG. 5B, the arrow on each of axes,
A.sub.N, indicates the direction of each lateral jet from feed
injection nozzles 322a-d toward the axis, A.sub.U, of upper venturi
310. As shown, each of feed injection nozzles 322a-d of a given
feed injection array 320 may be spaced equi-radially from the axis,
A.sub.U, of upper venturi 310. FIG. 5B shows a feed injection array
320 having four evenly spaced feed injection nozzles 322a-d, e.g.,
for clarity of illustration. In practice, each feed injection array
320 may comprise other (e.g., greater) numbers, and other
arrangements, of feed injection nozzles 322.
[0114] FIG. 6A shows, in sectional view, an inter-venturi channel
in relation to an upper venturi and a lower venturi of a mixing
device 300, and FIG. 6B shows the inter-venturi channel in relation
to the upper venturi outlet and the lower venturi inlet as seen
along the line 6B-6B of FIG. 6A. Upper venturi 310 has an axial
outlet 314 at upper venturi distal end 310b and lower venturi 330
has an axial inlet 332 at lower venturi proximal end 330a (see, for
example, FIGS. 3A-4B). In an embodiment, lower venturi inlet 332 is
spaced radially outward from upper venturi outlet 314 to define an
inter-venturi channel 350 between lower venturi proximal end 330a
and upper venturi distal end 310b. Each of lower venturi inlet 332
and upper venturi outlet 314 may be at least substantially
circular. In an embodiment, inter-venturi channel 350 may be
substantially annular (see, for example, FIG. 6B). In an
embodiment, inter-venturi channel 350 allows the flow of an
internal recirculation stream of reactor vessel 200, wherein the
internal recirculation stream may flow downward through
inter-venturi channel 350 into lower venturi 330 and out of lower
venturi outlet 334.
[0115] With further reference to FIG. 6A, the flow of the internal
recirculation stream through inter-venturi channel 350 is indicated
by the arrows labeled R.sub.I, while the external recirculation
stream flowing from upper venturi outlet 314 is indicated by the
arrows labeled R.sub.E. The flow of the internal recirculation
stream of reactor vessel 200, e.g., through inter-venturi channel
350 and lower venturi 330, may further promote mixing of the
reactor contents comprising a multiphase reaction system, such as
an emulsion of an ionic liquid catalyst in a hydrocarbon mixture.
In an embodiment, the ratio of the flow rate (vol. per unit time)
of the internal recirculation stream to the flow rate of the
external recirculation stream may be in the range from 0.1 to 10,
or from 0.2 to 5, or from 0.25 to 4.
[0116] FIG. 7A schematically represents a mixing device, in
sectional view, and FIG. 7B shows a feed injection array of the
mixing device as seen along the line 7B-7B of FIG. 7A. Mixing
device 300 of FIGS. 7A-7B may comprise an upper venturi 310 and a
lower venturi 330, e.g., as described with reference to FIGS.
3A-4B. Mixing device 300 may be disposed in reactor vessel 200 in a
vertical orientation such that only a proximal portion of upper
venturi 310 is disposed above reactor vessel top 202. A distal
portion of upper venturi 310 may be disposed below reactor vessel
top 202 and sealingly engaged therewith.
[0117] With further reference to FIGS. 7A-7B, mixing device 300 may
comprise a jacket 380 surrounding a distal portion of upper venturi
310. Jacket 380 may be disposed radially outward from upper venturi
310 to define an annular feed conduit 384. Jacket 380 may have a
jacket proximal end 380a. In an embodiment, jacket proximal end
380a may be sealingly engaged with the underside of reactor vessel
top 202. Jacket 380 may include a jacket base 382 at jacket distal
end 380b. Jacket base 382 may be sealed against upper venturi 310
at, or adjacent to, upper venturi distal end 310b. A plurality of
feed injection nozzles 322 may extend distally of jacket base 382
to define a feed injection array 320 (see, for example, FIG. 7B).
Feed conduit 384 may be in fluid communication with a feed supply
line 390 for receiving hydrocarbon feed 301, and each feed
injection nozzle 322 may be in fluid communication with feed
conduit 384 for the projection of a lateral jet of the hydrocarbon
feed from each of feed injection nozzles 322. In an embodiment,
each lateral jet of hydrocarbon feed may be projected toward the
upper venturi axis, A.sub.U, such that each lateral jet collides
with the central jet projected from upper venturi outlet 314.
Mixing devices for system 100 as disclosed herein are not limited
to a particular feed conduit configuration.
[0118] With further reference to FIG. 7B, in an embodiment feed
injection nozzles 322 may be arranged so as to provide an annular
and/or symmetrical feed injection array 320. Each feed injection
nozzle 322 of feed injection array 320 may have a nozzle outlet 324
(see, for example, FIGS. 9A and 11A-11B). Although nozzles 322 are
shown in FIG. 7B as terminating radially outward from the perimeter
314' of upper venturi outlet 314, in other embodiments feed
injection nozzles 322 may extend radially inward to, or beyond, the
perimeter 314' of upper venturi outlet 314.
[0119] Without reference to a particular figure or embodiment,
mixing device 300 may be configured for projecting a central jet of
an external recirculation stream (arrow R.sub.E) downward from
upper venturi outlet 314 into lower venturi 330. In an embodiment,
the flow rate of the external recirculation stream may be in the
range from 2 to 50 times the flow rate of hydrocarbon feed 301, or
from 2 to 25 times the flow rate of hydrocarbon feed 301, or from 4
to 10 times the flow rate of hydrocarbon feed 301. In an
embodiment, upper venturi 310 may be configured, e.g., suitably
tapered, such that a pressure drop across upper venturi outlet 314
may be up to about 110 psi; in a sub-embodiment the pressure drop
across upper venturi outlet 314 may be in the range from 10 to 110
psi, or from 50 to 80 psi. It is to be understood that the drawings
are schematic representations that may not be drawn to scale and do
not represent a specific design of the upper venturi or other
components.
[0120] The external recirculation stream, R.sub.E, supplied to
upper venturi inlet 312 may comprise ionic liquid catalyst in
combination with unreacted hydrocarbons. In an embodiment, the
pressure drop across upper venturi outlet 314 may produce an ionic
liquid/hydrocarbon emulsion comprising small to microscopic
droplets of the ionic liquid catalyst, e.g., having an ionic liquid
catalyst droplet diameter in the range from 1 to 1000 microns, or
from 5 to 250 microns, or from 10 to 150 microns. Thus, the central
jet of the external recirculation stream projected from upper
venturi outlet 314 may comprise such an emulsion having small to
microscopic droplets of the ionic liquid catalyst dispersed in the
unreacted hydrocarbons. Such droplets may provide not only an ionic
liquid catalyst surface area that will produce a high rate of
reaction and a high quality product (e.g., alkylate), but also a
hydrocarbon/ionic liquid mixed phase that is conducive to
subsequent phase separation downstream.
[0121] FIG. 8A schematically represents a portion of a mixing
device, in sectional view, and FIG. 8B shows a feed injection array
of the mixing device, as seen along the line 8B-8B of FIG. 8A.
Embodiments represented by FIGS. 8A-8B may have certain elements,
features, and characteristics as described hereinabove, e.g., with
reference to FIGS. 7A-7B. Lower venturi 330 is omitted from FIG. 8A
for the sake of clarity. In an embodiment represented by FIGS.
8A-8B, feed injection array 320 may be configured such that the
axis, A.sub.N, of each feed injection nozzle 322 intersects the
axis, A.sub.U, of upper venturi 310 at an angle, .theta., of about
90.degree. or substantially at a right angle. Accordingly, in an
embodiment the axis, A.sub.N, of each feed injection nozzle 322 may
be at least substantially parallel to a plane defined by upper
venturi outlet 314. Embodiments in which the axis of each feed
injection nozzle 322 is orthogonal, or at least substantially
orthogonal, to the axis of upper venturi 310 are not restricted to
any particular feed conduit configuration(s).
[0122] In an embodiment, e.g., as shown in FIGS. 8A-8B, each feed
injection nozzle 322 may terminate at a location radially inward
from the perimeter 314' of upper venturi outlet 314, such that the
central jet projected from upper venturi outlet 314 may collide
with at least a terminal portion of each feed injection nozzle 322.
Although feed injection nozzles 322 are shown in FIG. 8B as
extending radially inward of the perimeter 314' of upper venturi
outlet 314, in other embodiments feed injection nozzles 322 may
terminate radially outward from perimeter 314' of upper venturi
outlet 314, or feed injection nozzles 322 may terminate
equi-radially with perimeter 314' of upper venturi outlet 314.
[0123] FIG. 9A schematically represents a portion of a mixing
device, and FIG. 9B is an enlarged view showing a feed injection
array of the mixing device as seen along the line 9B-9B of FIG. 9A.
In FIG. 9A lower venturi 330 is omitted and the upper venturi 310
is truncated for the sake of clarity of illustration. Mixing device
300 may be disposed in reactor vessel 200 in a vertical orientation
such that only a proximal portion of upper venturi 310 is disposed
above reactor vessel top 202.
[0124] With further reference to FIGS. 9A-9B, in an embodiment
mixing device 300 may comprise a feed injection array 320
comprising a plurality of feed injection nozzles 322. Each feed
injection nozzle 322 may be in fluid communication with a feed
injection manifold 386. In an embodiment, feed injection manifold
386 may be at least substantially annular. Feed injection manifold
386 may be in fluid communication with a feed supply line 390,
e.g., via a tubular feed conduit 384', for distributing hydrocarbon
feed to each of feed injection nozzles 322. In an embodiment, feed
injection nozzles 322 may extend distally of (below) feed injection
manifold 386. In an embodiment, tubular feed conduit 384' may be
disposed laterally of upper venturi 310.
[0125] With further reference to FIG. 9B, in an embodiment feed
injection nozzles 322 may be arranged so as to provide an annular
and/or symmetrical feed injection array 320. As shown in FIG. 9A,
each feed injection nozzle 322 may have a nozzle outlet 324 for the
projection therefrom of a lateral jet of hydrocarbon feed. In an
embodiment, a nozzle outlet 324 may be axially located at the
terminus 322' of each feed injection nozzle 322 (see, for example,
FIGS. 11A-11B). In an embodiment, each lateral jet may be projected
toward the axis of upper venturi 310, such that each lateral jet
collides with a central jet of liquid projected from upper venturi
outlet 314.
[0126] FIG. 10 schematically represents, in sectional view, a lower
venturi for a mixing device having a feed injection array at the
same elevation or about the same elevation as a constriction point
of the lower venturi. Lower venturi 330 may have an axial inlet 332
at lower venturi proximal end 330a and an axial outlet 334 at lower
venturi distal end 330b. Lower venturi 330 may further have a lower
venturi constriction point 336, wherein lower venturi constriction
point 336 may be disposed between lower venturi proximal end 330a
and lower venturi distal end 330b, i.e., at an elevation below
lower venturi inlet 332 and above lower venturi outlet 334. A feed
injection array 320 may be disposed at the same elevation or about
the same elevation as lower venturi constriction point 336. Feed
injection array 320 may comprise a plurality of feed injection
nozzles 322. Each feed injection nozzle 322 may be in fluid
communication with a feed conduit (see, e.g., FIG. 9A) for
supplying hydrocarbon feed to feed injection nozzles 322.
[0127] With further reference to FIG. 10, each feed injection
nozzle 322 may extend into the interior of lower venturi 330. Each
feed injection nozzle 322 may project a lateral jet of hydrocarbon
feed, into lower venturi 330, at the same elevation or about the
same elevation as lower venturi constriction point 336. Liquid
flowing through lower venturi 330, e.g., a mixture of the internal-
and external recirculation streams of the reactor vessel, may
collide with each lateral jet of feed injection array 320. In an
embodiment, liquid flowing through lower venturi 330 may also
collide with a terminal portion of each feed injection nozzle 322.
Feed injection array 320 may be configured such that the axis of
each feed injection nozzle 322 may intersect the axis, A.sub.L, of
lower venturi 330, substantially as described with reference to
FIGS. 5A-5B, supra, wherein lower venturi 330 may be coaxial with
upper venturi 310. Two feed injection nozzles are shown in FIG. 10
for the sake of clarity of illustration; in practice, feed
injection array 320 may comprise a greater number of annularly
arranged feed injection nozzles 322, e.g., as described
hereinabove.
[0128] FIG. 11A shows, in perspective view, a terminal portion of a
feed injection nozzle 322, and FIG. 11B is an enlarged view of a
nozzle outlet 324 of feed injection nozzle 322 as seen along the
line 11B-11B of FIG. 11A. In an embodiment, nozzle outlet 324 may
be axially disposed at the terminus 322' of feed injection nozzle
322, such that the center of nozzle outlet 324 coincides with the
axis, A.sub.N, of feed injection nozzle 322. In an embodiment,
nozzle outlet 324 may be at least substantially circular or round.
Other configurations and shapes for feed injection nozzles 322 and
nozzle outlets 324 are also possible.
[0129] In the case of a feed injection array 320 disposed at the
same elevation or about the same elevation as the lower venturi
proximal end 330a, the terminus 322' of each feed injection nozzle
322 may be at the same radial location or about the same radial
location as the perimeter 314' of the upper venturi outlet 314. In
this context, the expression "the same radial location or about the
same radial location" means that terminus 322' of each feed
injection nozzle 322 may be disposed within a radial distance not
greater than (.ltoreq.) 0.2D.sub.UO radially inward or radially
outward from the perimeter 314' of upper venturi outlet 314 (see,
e.g., FIGS. 7B and 8B), wherein D.sub.UO is the diameter of upper
venturi outlet 314 (see, e.g., FIG. 4B).
[0130] In the case of a feed injection array 320 disposed at the
same elevation or about the same elevation as the lower venturi
constriction point 336, the terminus 322' of each feed injection
nozzle 322 may be spaced radially outward from the lower venturi
axis, A.sub.L, by a distance in the range from 0.2 to 0.5D.sub.LC,
or from 0.4D.sub.LC to 0.5D.sub.LC, wherein D.sub.LC is the
internal diameter of the lower venturi constriction point 336.
[0131] For a given feed injection array 320, all of the nozzle
outlets 324 may be at the same elevation or substantially the same
elevation (see, e.g., FIG. 9A). In this disclosure and the appended
claims, the elevation of a given feed injection array, e.g.,
relative to the lower venturi, may be defined as, or referenced to,
the elevation of the center of nozzle outlets 324 of that feed
injection array.
[0132] FIG. 12A schematically represents a mixing device 300'
comprising an upper venturi 310, a feed injection annulus 370, and
a lower venturi 330. In an embodiment, upper venturi 310 may be
disposed vertically within reactor vessel top 202. Upper venturi
310 may be affixed to, and sealingly engaged with, reactor vessel
top 202.
[0133] In FIG. 12A the axis of upper venturi 310 is indicated by
the line labeled A.sub.U. Lower venturi 330 may be coaxial with
upper venturi 310. In an embodiment, lower venturi 330 may be
affixed to upper venturi 310, e.g., using suitable support
structures (not shown), such as steel bars, and the like. In an
embodiment, lower venturi proximal end 330a may be disposed at the
same elevation or about the same elevation as upper venturi distal
end 310b, e.g., as described hereinabove (see, for example, FIG.
3B). In FIG. 12A, lower venturi proximal end 330a may be shown
below upper venturi distal end 310b for the sake of clarity of
illustration.
[0134] In an embodiment, feed injection annulus 370 may be at the
same elevation or about the same elevation as lower venturi
proximal end 330a, e.g., as described hereinabove (see, for
example, FIG. 4B). Mixing device 300' is not limited to a
particular elevation or location of feed injection annulus 370. In
an embodiment, upper venturi distal end 310b, feed injection
annulus 370, and lower venturi 330 may be disposed within reactor
vessel 200. In an embodiment, feed injection annulus 370 may be
disposed coaxially with both upper venturi 310 and lower venturi
330. Feed injection annulus 370 may be affixed, attached, or
coupled to upper venturi 310 and/or to lower venturi 330.
[0135] FIG. 12B schematically represents a portion of a mixing
device 300' having a feed injection annulus 370, FIG. 12C shows the
feed injection annulus 370 as seen along the line 12C-12C of FIG.
12B, and FIGS. 12D-12G each show a feed injection annulus 370 as
seen in sectional view along the line 12D-G-12D-G of FIG. 12C
according various embodiments. In FIG. 12B lower venturi 330 is
omitted for the sake of clarity of illustration. In an embodiment,
mixing device 300' may be disposed in reactor vessel 200 in a
vertical orientation such that only a proximal portion of upper
venturi 310 is disposed above reactor vessel top 202.
[0136] With further reference to FIGS. 12B-12C, feed injection
annulus 370 may be in fluid communication with a feed supply line
390, e.g., via a tubular feed conduit 384', for providing
hydrocarbon feed 301 to mixing device 300'. In an embodiment,
tubular feed conduit 384' may be disposed laterally of upper
venturi 310. Feed injection annulus 370 may have an annulus inner
portion 370a and an annulus outer portion 370b. Each feed injection
annulus 370 may have one or more feed injection ports 372 at
annulus inner portion 370a (see, e.g., FIGS. 12D-12G).
[0137] With reference to FIGS. 12B-12G, feed injection annulus 370
may be configured so as to provide an annular and/or symmetrical
projection of a second liquid from at least one feed injection port
372 toward the axis, A.sub.U, of upper venturi 310. In an
embodiment, feed injection annulus 370 may be configured such that
the second liquid is projected from the at least one feed injection
port 372 as at least one jet that collides with a central jet of a
first liquid projected from upper venturi distal end 310b.
According to an embodiment, the projection of the second liquid
from feed injection annulus 370 toward upper venturi axis, A.sub.u,
may be indicated in FIG. 12C by the arrows labeled L.sub.2.
According to various sub-embodiments, the arrows labeled L.sub.2 in
FIG. 12C may represent a single (e.g., annular) jet, or a plurality
of up to four jets, or a plurality of more than four jets of the
second liquid.
[0138] FIG. 12D is a sectional view of a feed injection annulus 370
having a feed injection port 372 in the form of an annular slit at
annulus inner portion 370a. FIG. 12E is a sectional view of a feed
injection annulus 370 having a plurality of feed injection ports
372 in the form of arcuate slits at annulus inner portion 370a.
FIG. 12F is a sectional view of a feed injection annulus 370 having
a plurality of feed injection ports 372 at annulus inner portion
370a, wherein feed injection ports 372 may be at least
substantially circular. Although feed injection ports 372 in the
embodiments of FIGS. 12D-12F are shown as being disposed
substantially at the horizontal midline, M, of feed injection
annulus 370 (see, e.g., FIG. 12G), other locations for feed
injection ports 372 are also possible.
[0139] FIG. 12G is a sectional view of a feed injection annulus 370
having a plurality of feed injection ports 372. The enlarged
projection at the right of FIG. 12G shows the horizontal midline,
M, of feed injection annulus 370. In an embodiment, feed injection
ports 372 may be disposed at various locations on annulus inner
portion 370a spanning an angular range from 0 to 45.degree. above
or below the horizontal midline, M, i.e., a may be in the range
from 0 to 45.degree.. In an embodiment, each feed injection annulus
370 may have from two (2) to 50 feed injection ports 372, or from
four (4) to 40 feed injection ports 372, or from six (6) to 30 feed
injection ports 372. Feed injection annuli 370 are not limited to
any one type of feed injection port 372, and a given feed injection
annulus 370 may have two or more different types of feed injection
ports 372 in various combinations.
[0140] In an embodiment, the first liquid comprising the central
jet from the upper venturi outlet may comprise an external
recirculation stream of the reactor vessel, and the second liquid
may comprise a hydrocarbon feed. In an embodiment, the external
recirculation stream may comprise reactor effluent in combination
with added fresh ionic liquid catalyst, wherein the reactor
effluent may have been cooled in a circulation loop before or after
the addition of the fresh ionic liquid catalyst. In an embodiment,
the ionic liquid catalyst may comprise, e.g., a chloroaluminate
ionic liquid as described hereinbelow. In an embodiment, the
hydrocarbon feed may comprise at least one of an olefin feed
stream, an isoparaffin feed stream, and a mixed olefin/isoparaffin
feed, for ionic liquid catalyzed alkylation, e.g., as also
described hereinbelow.
[0141] FIG. 13 schematically represents a system and process for
ionic liquid catalyzed hydrocarbon conversion, according to another
embodiment. System 100' of FIG. 13 may comprise a reactor vessel
200 having a reactor vessel top 202, a reactor vessel base 203, and
a vessel outlet 204; and one or more mixing devices 300/300'
disposed at reactor vessel top 202 (see, for example, FIGS. 2-12G).
System 100' may have elements and features in common with system
100 (see, for example, FIG. 1D). In reactor vessel 200, at least
one isoparaffin and at least one olefin may be contacted with ionic
liquid catalyst under ionic liquid alkylation conditions. Ionic
liquid alkylation conditions, feedstocks, and ionic liquid
catalysts that may be suitable for performing ionic liquid
alkylation reactions are described, for example, hereinbelow.
[0142] In an embodiment, a process for ionic liquid catalyzed
hydrocarbon conversion may include adding a co-catalyst, or a
catalyst promoter, or both a catalyst promoter and a co-catalyst,
to reactor vessel 200. In an embodiment, such a co-catalyst may
comprise an alkyl chloride. A catalyst promoter for addition to the
modular reactor may comprise a hydrogen halide, such as HCl. In an
embodiment, a co-catalyst and/or a catalyst promoter may be fed to
reactor vessel 200 via the hydrocarbon feed, or via the ionic
liquid catalyst feed, or by separate direct injection into reactor
vessel 200. The addition of co-catalyst(s) and/or catalyst
promoter(s) to reactor vessel 200 is not shown in the Drawings.
Various methods and techniques for introducing co-catalyst(s)
and/or catalyst promoter(s) to reactor vessel 200 will be apparent
to the skilled artisan.
[0143] System 100' may further comprise a circulation loop 400.
Circulation loop 400 may comprise a first loop end 400a coupled to
vessel outlet 204 and a second loop end 400b coupled to mixing
device 300/300'. Circulation loop 400 may further comprise a
circulation pump 406, and a heat exchanger 408. Circulation loop
400 may still further comprise at least one circulation loop
conduit 410, e.g., for coupling components of circulation loop 400
to vessel outlet 204 and mixing device 300/300'.
[0144] System 100' may still further comprise an ionic
liquid/hydrocarbon (IL/HC) separator 500 in fluid communication
with circulation loop 400, and a fractionation unit 600 in fluid
communication with IL/HC separator 500. Reactor effluent 206 may be
withdrawn from reactor vessel 200 into circulation loop 400 via
vessel outlet 204. A portion of the reactor effluent 206 may be fed
from circulation loop 400, via a line 501, to IL/HC separator 500
for separation of the portion of reactor effluent into a
hydrocarbon phase 502 and an ionic liquid phase 403'. Non-limiting
examples of separation processes that can be used for such phase
separation include coalescence, phase separation, extraction,
membrane separation, and partial condensation. IL/HC separator 500
may comprise, for example, one or more of the following: a settler,
a coalescer, a centrifuge, a cyclone, a distillation column, a
condenser, and a filter. In an embodiment, IL/HC separator 500 may
comprise a gravity based settler and a coalescer disposed
downstream from the gravity based settler.
[0145] It can be seen from FIG. 13 that IL/HC separator 500 may be
external to circulation loop 400. In an embodiment, circulation
loop 400 may lack a unit or apparatus for phase separation of
reactor effluent 206 or the external recirculation stream, R.sub.E.
Accordingly, reactor effluent 206 may be recirculated to reactor
vessel 200 without any attempt to separate reactor effluent 206, or
the external recirculation stream, within circulation loop 400.
System 100' having IL/HC separator 500 external to circulation loop
400 allows IL/HC separator 500 to be smaller than that for a system
in which a separator may be used for phase separation of 100% of
the withdrawn reactor effluent within a hydrocarbon recycle
loop.
[0146] The hydrocarbon phase 502 from IL/HC separator 500 may be
fed via a line 503 to fractionation unit 600. The hydrocarbon phase
from IL/HC separator 500 may comprise alkylate components
(product), as well as unreacted components of hydrocarbon feed 301,
including isobutane. The alkylate components may comprise, e.g.,
C.sub.5-C.sub.11 alkanes, such as C.sub.7-C.sub.8 isoparaffins. The
hydrocarbon phase from IL/HC separator 500 may be fractionated via
fractionation unit 600 to provide one or more products 602a-n and
an isobutane fraction. In an embodiment, products 602a-n may
comprise alkylate, n-butane, and propane. In an embodiment,
fractionation unit 600 may comprise one or more distillation
columns.
[0147] At least a portion of the isobutane stream from
fractionation unit 600 may be recycled via a line 604 to mixing
device(s) 300/300' and reactor vessel 200. In an embodiment, the
recycle isobutane may be premixed with at least one of an olefin
feed stream 301a and a make-up isobutane feed stream 301b to
provide a mixed hydrocarbon feed 301 for injection into reactor
vessel 200 via the one or mixing devices 300/300'.
[0148] The ionic liquid phase 403' from IL/HC separator 500 may be
recycled to circulation loop 400 via a line 505. Make-up (fresh)
ionic liquid catalyst 403 may be combined with the recycled ionic
liquid catalyst via a line 509. The combined fresh and recycled
ionic liquid catalyst may be injected into the reactor effluent
within circulation loop 400 to provide an external recirculation
stream, R.sub.E, which may be cooled via heat exchanger 408. The
cooled external recirculation stream may be recirculated to reactor
vessel 200 via circulation loop 400 and mixing device(s) 300/300'.
In an embodiment, the ionic liquid catalyst may be added to system
100' at a rate sufficient to maintain the overall ionic liquid
catalyst volume in reactor vessel 200 in the range from 0.5 to 50
vol %, or from 1 to 10 vol %, or from 2 to 6 vol %.
[0149] In an embodiment, the ionic liquid phase 403' may be
recycled to circulation loop 400 either directly or indirectly
through a catalyst surge vessel (the latter not shown). In an
embodiment, a portion of the ionic liquid phase 403' from IL/HC
separator 500 may be purged or withdrawn to other vessels (not
shown), via a line 507, for ionic liquid catalyst regeneration,
e.g., as described hereinbelow.
Feedstocks for Ionic Liquid Catalyzed Alkylation
[0150] In an embodiment, feedstocks for ionic liquid catalyzed
alkylation may comprise various olefin- and isoparaffin containing
hydrocarbon streams in or from one or more of the following: a
petroleum refinery, a gas-to-liquid conversion plant, a
coal-to-liquid conversion plant, a naphtha cracker, a middle
distillate cracker, a natural gas production unit, an LPG
production unit, and a wax cracker, and the like.
[0151] Examples of olefin containing streams include FCC off-gas,
coker gas, olefin metathesis unit off-gas, polyolefin gasoline unit
off-gas, methanol to olefin unit off-gas, FCC light naphtha, coker
light naphtha, Fischer-Tropsch unit condensate, and cracked
naphtha. Some olefin containing feed streams may contain at least
one olefin selected from ethylene, propylene, butylenes, pentenes,
and up to C.sub.10 olefins, i.e., C.sub.2-C.sub.10 olefins, and
mixtures thereof. Such olefin containing streams are further
described, for example, in U.S. Pat. No. 7,572,943, the disclosure
of which is incorporated by reference herein in its entirety.
[0152] Examples of isoparaffin containing streams include, but are
not limited to, FCC naphtha, hydrocracker naphtha, coker naphtha,
Fisher-Tropsch unit condensate, natural gas condensate, and cracked
naphtha. Such streams may comprise at least one C.sub.4-C.sub.10
isoparaffin. In an embodiment, such streams may comprise a mixture
of two or more isoparaffins. In a sub-embodiment, an isoparaffin
feed to the alkylation reactor during an ionic liquid catalyzed
alkylation process may comprise isobutane.
Paraffin Alkylation
[0153] In an embodiment, the alkylation of a mixture of
hydrocarbons may be performed in a reactor vessel under conditions
known to produce alkylate gasoline, and the reactor vessel may be
referred to herein as an alkylation reactor or alkylation zone. The
alkylation conditions in the alkylation reactor are selected to
provide the desired product yields and quality. The alkylation
reaction in the alkylation reactor is generally carried out in a
liquid hydrocarbon phase, in a batch system, a semi-batch system,
or a continuous system. The catalyst volume in the alkylation
reactor may be in the range of 0.5 to 50 vol %, or from 1 to 10 vol
%, or from 2 to 6 vol %. In an embodiment, vigorous mixing can be
attained by using one or more mixing devices per reactor vessel,
e.g., as described hereinabove, to provide contact between the
hydrocarbon reactants and ionic liquid catalyst over a large
surface area per unit volume of the reactor vessel. The alkylation
reaction temperature can be in the range from -40.degree. C. to
150.degree. C., such as -20.degree. C. to 100.degree. C., or
-15.degree. C. to 50.degree. C. The alkylation pressure can be in
the range from atmospheric pressure to 8000 kPa. In an embodiment
the alkylation pressure is maintained at a level at least
sufficient to keep the reactants in the liquid phase. The residence
time of reactants in the reactor can be in the range of a second to
60 hours.
[0154] In one embodiment, the molar ratio of isoparaffin to olefin
in the alkylation reactor can vary over a broad range. Generally
the molar ratio of isoparaffin to olefin is in the range of from
0.5:1 to 100:1. For example, in different embodiments the molar
ratio of isoparaffin to olefin is from 1:1 to 50:1, from 1.1:1 to
10:1, or from 1.1:1 to 20:1. Lower isoparaffin to olefin molar
ratios will tend to produce a higher yield of higher molecular
weight alkylate products, and thus can be selected when operating
the alkylation reactor in a distillate mode, such as described in
U.S. Patent Publication No. US20110230692A1.
Other Hydrocarbon Conversion Processes
[0155] Systems as disclosed herein can be used for other
hydrocarbon conversion processes using an acidic ionic liquid
catalyst. Some examples of the hydrocarbon conversion processes
include isomerization of C.sub.4-C.sub.8 paraffins wherein normal
paraffins are converted to isoparaffins, oligomerization of
C.sub.3-C.sub.30 olefins to produce higher molecular weight
olefins, isomerization of C.sub.3-C.sub.30 olefins to shift the
location of the double bond in the molecule (double bond
isomerization) or shift the back-bone of the olefin molecules
(skeletal isomerization), cracking of high molecular weight olefins
and paraffins to low molecular paraffins and olefins, and
alkylation of olefins with aromatics to form alkylaromatics.
Ionic Liquid Catalysts for Hydrocarbon Conversion Processes
[0156] In an embodiment, a catalyst for hydrocarbon conversion
processes may be a chloride-containing ionic liquid catalyst
comprised of at least two components which form a complex. A first
component of the chloride-containing ionic liquid catalyst can
comprise a Lewis Acid selected from components such as Lewis Acidic
compounds of Group 13 metals, including aluminum halides, alkyl
aluminum halides, gallium halides, alkyl gallium halides, indium
halides, and alkyl indium halides (see International Union of Pure
and Applied Chemistry (IUPAC), version 3, October 2005, for Group
13 metals of the periodic table). Other Lewis Acidic compounds, in
addition to those of Group 13 metals, can also be used. In one
embodiment the first component is aluminum halide or alkyl aluminum
halide. For example, aluminum trichloride can be the first
component of the chloride-containing ionic liquid catalyst.
[0157] A second component comprising the chloride-containing ionic
liquid catalyst is an organic salt or mixture of salts. These salts
can be characterized by the general formula Q.sup.+A.sup.-, wherein
Q.sup.+ is an ammonium, phosphonium, boronium, iodonium, or
sulfonium cation and A.sup.- is a negatively charged ion such as
Cl.sup.-, Br.sup.-, ClO.sub.4.sup.-, NO.sub.3.sup.-,
BF.sub.4.sup.-, BCl.sub.4.sup.-, PF.sub.6.sup.-, SbF.sub.6.sup.-,
AlCl.sub.4.sup.-, TaF.sub.6.sup.-, CuCl.sub.2.sup.-,
FeCl.sub.3.sup.-, HSO.sub.3.sup.-, RSO.sub.3.sup.- (wherein R is an
alkyl group having from 1 to 12 carbon atoms),
SO.sub.3CF.sub.3.sup.-, and .sub.3.sup.-sulfurtrioxyphenyl. In one
embodiment, the second component is selected from those having
quaternary ammonium or phosphonium halides containing one or more
alkyl moieties having from 1 to 12 carbon atoms, such as, for
example, trimethylamine hydrochloride, methyltributylammonium
halide, trialkylphosphonium hydrochloride, tetraalkylphosphonium
chlorides, methyltrialkylphosphonium halide or substituted
heterocyclic ammonium halide compounds, such as hydrocarbyl
substituted pyridinium halide compounds, for example,
1-butylpyridinium halide, benzylpyridinium halide, or hydrocarbyl
substituted imidazolium halides, such as for example,
1-ethyl-3-methyl-imidazolium chloride.
[0158] In one embodiment the chloride-containing ionic liquid
catalyst is selected from the group consisting of hydrocarbyl
substituted pyridinium chloroaluminate, hydrocarbyl substituted
imidazolium chloroaluminate, quaternary amine chloroaluminate,
trialkyl amine hydrogen chloride chloroaluminate, alkyl pyridine
hydrogen chloride chloroaluminate, and mixtures thereof. For
example, the chloride-containing ionic liquid catalyst can be an
acidic haloaluminate ionic liquid, such as an alkyl substituted
pyridinium chloroaluminate or an alkyl substituted imidazolium
chloroaluminate of the general formulas A and B, respectively.
##STR00001##
[0159] In the formulas A and B, R, R.sub.1, R.sub.2, and R.sub.3
are H, methyl, ethyl, propyl, butyl, pentyl or hexyl group, and X
is a chloroaluminate. In the formulas A and B, R, R.sub.1, R.sub.2,
and R.sub.3 may or may not be the same. In one embodiment the
chloride-containing ionic liquid catalyst is N-butylpyridinium
chloroaluminate. Examples of highly acidic chloroaluminates are
Al.sub.2Cl.sub.7.sup.- and Al.sub.3Cl.sub.10.sup.-.
[0160] In another embodiment the chloride-containing ionic liquid
catalyst can have the general formula RR'R''NH.sup.+
Al.sub.2Cl.sub.7.sup.-, wherein R, R', and R'' are alkyl groups
containing from 1 to 12 carbons, and where R, R', and R'' may or
may not be the same.
[0161] In another embodiment the chloride-containing ionic liquid
catalyst can have the general formula RR'R''R'''P.sup.+
Al.sub.2Cl.sub.7.sup.-, wherein R, R', R'' and R''' are alkyl
groups containing from 1 to 12 carbons, and wherein R, R', R'' and
R''' may or may not be the same.
[0162] The presence of the first component should give the
chloride-containing ionic liquid a Lewis or Franklin acidic
character. Generally, the greater the mole ratio of the first
component to the second component, the greater is the acidity of
the chloride-containing ionic liquid catalyst. The molar ratio of
the first component (metal halide) to the second component
(quaternary amine or quaternary phosphorus) is in the range of 2:1
to 1.1:1.
[0163] In one embodiment, the chloride-containing ionic liquid
catalyst is mixed in the alkylation reactor with a hydrogen halide
and/or an organic halide. The hydrogen halide or organic halide can
boost the overall acidity and change the selectivity of the
chloride-containing ionic liquid catalyst. The organic halide can
be an alkyl halide. The alkyl halides that can be used include
alkyl bromides, alkyl chlorides, alkyl iodides, and mixtures
thereof. A variety of alkyl halides can be used. Alkyl halide
derivatives of the isoparaffins or the olefins that comprise the
feed streams in the alkylation process are good choices. Such alkyl
halides include, but are not limited to, isopentyl halides,
isobutyl halides, butyl halides (e.g., 1-butyl halide or 2-butyl
halide), propyl halides and ethyl halides. Other alkyl chlorides or
halides having from 1 to 8 carbon atoms can be also used. The alkyl
halides can be used alone or in combination with hydrogen halide.
The alkyl halide or hydrogen halide is fed to the unit by injecting
the alkyl halide or hydrogen halide to the hydrocarbon feed, or to
the ionic liquid catalyst, or to the alkylation reactor directly.
The amount of HCl or alkylation chloride usage, the location of the
injection, and the injection method may affect the amount of
organic chloride side-product formation. The use of alkyl halides
to promote hydrocarbon conversion by chloride-containing ionic
liquid catalysts is taught in U.S. Pat. No. 7,495,144 and in U.S.
Patent Publication No. 20100298620A1.
[0164] It is believed that the alkyl halide decomposes under
hydrocarbon conversion conditions to liberate Bronsted acids or
hydrogen halides, such as hydrochloric acid (HCl) or hydrobromic
acid (HBr). These Bronsted acids or hydrogen halides promote the
hydrocarbon conversion reaction. In one embodiment the halide in
the hydrogen halide or alkyl halide is chloride. In one embodiment
the alkyl halide is an alkyl chloride, for example t-butyl
chloride. Hydrogen chloride and/or an alkyl chloride can be used
advantageously, for example, when the chloride-containing ionic
liquid catalyst is a chloroaluminate.
Ionic Liquid Catalyst Regeneration
[0165] As a result of use, ionic liquid catalysts become
deactivated, i.e., lose activity, and may eventually need to be
replaced. However, ionic liquid catalysts are expensive and
replacement adds significantly to operating expenses. Thus it is
desirable to regenerate the ionic liquid catalyst on-line and reuse
it in the alkylation process. The regeneration of acidic ionic
liquid catalysts is taught in U.S. Pat. No. 7,651,970, US
7,674,739, US 7,691,771, US 7,732,363, and US 7,732,364.
[0166] Alkylation processes utilizing an ionic liquid catalyst form
by-products known as conjunct polymers. These conjunct polymers are
highly unsaturated molecules and deactivate the ionic liquid
catalyst by forming complexes with the ionic liquid catalyst. A
portion of used ionic liquid catalyst from the alkylation reactor
is sent to a regenerator reactor (not shown), which removes the
conjunct polymer from the ionic liquid catalyst and recovers the
activity of the ionic liquid catalyst. The regeneration reactor
contains metal components that saturates the conjunct polymers and
releases the saturated polymer molecules from the ionic liquid
catalyst. The regeneration can be performed either in a stirred
reactor or a fixed bed reactor. For ease of operation, a fixed bed
reactor may be used, even though the fixed bed regenerator reactor
is more susceptible to plugging from coking, deposits of corrosion
products and decomposition products derived from feed contaminants.
A guard bed vessel containing adsorbent material with appropriate
pore size may be added before the regeneration reactor to minimize
contaminants going into the regeneration reactor.
Product Separation and Finishing
[0167] The hydrocarbon effluent product from the reactor containing
ionic liquid catalyst and hydrogen halide co-catalyst may contain
trace amounts of hydrogen halides or organic halides or inorganic
halides. When aluminum chloride containing catalyst is used, then
trace amounts of HCl, organic chlorides and inorganic chlorides may
be present in the reactor effluent. HCl and organic chlorides are
preferred to be captured and recycled to the alkylation reactor.
Inorganic chlorides such as corrosion products or decomposition
product may be captured with a filter.
[0168] The separated hydrocarbon product may still contain trace
amounts of HCl, organic chlorides and inorganic chlorides. Removal
of HCl and inorganic chlorides from the product are typically done
by caustic washing. Chloride selective adsorbent may be used to
capture the residual chlorides. Organic chloride may be converted
to HCl and organic hydrocarbon by hydrogenation, cracking or hot
caustic treating. Treating of products for chloride reduction is
taught, for example, in U.S. Pat. No. 7,538,256, US 7,955,498, and
US 8,327,004.
[0169] For the purposes of this specification and appended claims,
unless otherwise indicated, all numbers expressing quantities,
percentages or proportions, and other numerical values used in the
specification and claims, are to be understood as being modified in
all instances by the term "about." Furthermore, all ranges
disclosed herein are inclusive of the endpoints and are
independently combinable. Whenever a numerical range with a lower
limit and an upper limit are disclosed, any number falling within
the range is also specifically disclosed.
[0170] Any term, abbreviation or shorthand not defined is
understood to have the ordinary meaning used by a person skilled in
the art at the time the application is filed. The singular forms
"a," "an," and "the," include plural references unless expressly
and unequivocally limited to one instance.
[0171] All of the publications, patents and patent applications
cited in this application are herein incorporated by reference in
their entirety to the same extent as if the disclosure of each
individual publication, patent application or patent was
specifically and individually indicated to be incorporated by
reference in its entirety.
[0172] The drawings are representational and may not be drawn to
scale. Modifications of the exemplary embodiments disclosed above
may be apparent to those skilled in the art in light of this
disclosure. Accordingly, the invention is to be construed as
including all structure and methods that fall within the scope of
the appended claims. Unless otherwise specified, the recitation of
a genus of elements, materials or other components, from which an
individual component or mixture of components can be selected, is
intended to include all possible sub-generic combinations of the
listed components and mixtures thereof.
* * * * *